Table of contents
- Main points
- Coronavirus (COVID-19) and non-market services
- Non-market output and GDP during the COVID-19 pandemic
- Methods used to measure non-market output
- How national statistical institutes (NSIs) measure non-market output
- How the coronavirus (COVID-19) pandemic affected measures of non-market output
- Conclusions
- Annex: Predominant methods by country
- Authors and acknowledgements
- Related links
1. Main points
A variety of methodologies are employed by national statistical institutes (NSIs) to measure changes in the volume of non-market output, with direct input indicators generally used for public administration and defence and direct output indicators predominant for education and common for healthcare.
International comparisons of non-market output, and by extension gross domestic product (GDP), over the coronavirus (COVID-19) pandemic have been complicated by methodological differences.
Education services proved particularly difficult with a few countries implementing adjustments to estimates of output where it was perceived that the move to a remote learning environment led to a reduction in education output.
Despite differences in the methodologies used by different NSIs, there is a relationship between the intensity of the coronavirus pandemic in a country and the scale of the negative impact on non-market output, particularly for healthcare.
Additional discussions and refinement of the concepts used in the measurement of non-market services, especially for education, would assist in ensuring greater consistency between countries and likely benefit cross-country comparability.
3. Non-market output and GDP during the COVID-19 pandemic
The need to understand how the coronavirus (COVID-19) pandemic may have affected the measurement of non-market output originates from the contribution of non-market output to differences in changes in gross domestic product (GDP) across countries during the early stages of the coronavirus pandemic.
Although differences in the rate of GDP growth across countries are not unusual, the relative size of the differences observed in Quarter 2 (Apr to June) 2020 (for example, 9.5 percentage points between the UK and Germany) is extremely unusual, with COVID-19 fully entrenched in all G7 economies at this time.
This analysis focuses on Quarter 2 2020 when the first and most restrictive confinements were in place and a majority of OECD countries observed their largest, COVID-19 related impact on GDP. Figure 1 shows marked differences in GDP growth, especially for the headline volume estimates. In some countries, substantial variation is also visible between the growth rates of volume and current price estimates of GDP, possibly suggesting different price-level changes in countries during the coronavirus pandemic.
Figure 1: There was wide variation in gross domestic product growth during the first wave of the coronavirus (COVID-19) pandemic
Change in gross domestic product (GDP), quarter-on-quarter, Quarter 2 (Apr to June) 2020, G7 economies, current price and volume estimates
Source: Organisation for Economic Co-operation and Development – Quarterly National Accounts database
Notes:
- Data extracted on 4 February 2022.
Download this chart Figure 1: There was wide variation in gross domestic product growth during the first wave of the coronavirus (COVID-19) pandemic
Image .csv .xlsLooking at the expenditure components of GDP (see the article International comparisons of GDP during the coronavirus (COVID-19) pandemic for more detail), part of the difference in GDP growth arises from substantial variation in government final consumption expenditure (GFCE).
GFCE predominantly consists of services that are provided by governments for free or at prices that are not economically significant, referred to as non-market services (2008 SNA, section 2.40). Non-market services may include goods and services purchased at market price on behalf of households, who then receive them free or below economically significant prices.
Across G7 economies, the UK observed the largest increase in current price GFCE in Quarter 2 2020, while recording the largest decrease in volume terms (see Figure 2). In the other G7 economies – where GDP changes were more modest – movements in current price and volume GFCE have been more closely matched.
Figure 2: The UK had the largest decrease in the volume of government final consumption expenditure (GFCE) in Quarter 2 2020, and the largest increase in current price GFCE
Change in government final consumption expenditure (GFCE), quarter-on-quarter, Quarter 2 (Apr to June) 2020, G7 economies, current price and volume estimates
Source: Organisation for Economic Co-operation and Development – Quarterly National Accounts database
Notes:
- Data extracted on 4 February 2022.
Download this chart Figure 2: The UK had the largest decrease in the volume of government final consumption expenditure (GFCE) in Quarter 2 2020, and the largest increase in current price GFCE
Image .csv .xlsThe fall in volume GFCE in the UK, and to a lesser extent in France, in Quarter 2 2020 negatively affected real GDP growth. Figure 3 shows that the negative contribution for France and the UK in Quarter 2 2020 is offset in the third and fourth quarter, although quarterly growth remains more variable than in other countries.
Figure 3: The UK and France had substantial rebounds in government final consumption expenditure after a fall in Quarter 2 2020
Contribution (percentage points) of government final consumption expenditure (GFCE) to real gross domestic product (GDP) growth (quarter-on-quarter), Quarter 1 (Jan to Mar) 2020 to Quarter 3 (July to Sept) 2021, selected OECD economies, seasonally adjusted
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Notes:
- Data extracted 4 February 2022.
Download the data
The coronavirus pandemic’s effect on non-market services were similar in most OECD1 countries, with many experiencing an extended period of remote learning for schools and significant compositional shifts in healthcare services. Therefore, variations as observed in Figures 2 and 3 may involve differences in the measurement of non-market output and may not only reflect the impact of the coronavirus pandemic.
Most countries expect higher revisions of national accounts data than average for the period covering the coronavirus pandemic. In some cases, this is because shifts in measurement practice produced methodological splits between annual and quarterly national accounts. Even when methodological changes did not occur, differences between the indicators used for annual and quarterly compilation may have been exacerbated because of COVID-19. Because of this, a review of the non-market output ultimately recorded by countries once all annual data has been included may well prove useful to confirm that the trends observed above are still in place.
Notes for: Non-market output and GDP during the COVID-19 pandemic
- The OECD (Organisation for Economic Cooperation and Development) consists of the following countries: Australia, Austria, Belgium, Canada, Chile, Colombia, Costa Rica, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan, Korea, Latvia, Lithuania, Luxembourg, Mexico, Netherlands, New Zealand, Norway, Poland, Portugal, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, UK and US.
4. Methods used to measure non-market output
As non-market services are provided for free or at prices that are not economically significant, the measurement of their output poses unique challenges because of the lack of market prices. However, as noted by Schreyer (2010), regardless of whether services are provided by market or non-market units:
“The measured volume of non-market services should be the same as the one for measurement of the volume of market services, and vice-versa, as long as the services are the same.”
Therefore, different methods may be used to measure non-market output, given that the results closely approximate those that would have been observed if the service were provided by the market.
For many non-market services, there is ambiguity in quantifying what constitutes production. Are firefighters producing more output if they attend more fires, or is their state of readiness production in itself? If it takes the same inputs to incarcerate 10 prisoners as 11, should production increase with this additional inmate? What constitutes one unit of education output? Is it based on inputs, student numbers, or the quantity of learning conveyed?
Another conceptual challenge is how to assess changes in the quality of some non-market services. Many countries, including all EU member states and the UK, follow the guidance of the European System of Accounts (2010), which directs that estimates of non-market output not be adjusted for any change in quality. However, some non-EU countries may try to capture this within their estimates. In this regard, the distinction between quality and quantity change is also not always very clear. For example, does the quantity of education change if a class is divided and taught separately by a greater number of teachers, or would this result in a change in the quality of education?
While this article focuses on the compilation methods rather than the conceptual questions, some of these questions have become identifiable points of difference in how countries assessed the impact of the coronavirus pandemic on the delivery of non-market services.
The practical guidance for compiling non-market output is set out in key national accounts references, including:
- the 2008 System of National Accounts (SNA)
- the European System of Accounts 2010
- the Eurostat Handbook on prices and volume measures in the national accounts (2016)
- the OECD handbook Towards Measuring the Volume Output of Education and Health Services (2010)
This section briefly outlines current guidance for measuring current price and volume estimates of non-market output.
Current price estimates
The 2008 SNA (PDF, 9.1MB) defines market output in current price terms as “the value of goods and services sold at economically significant prices” (section 6.99). For units only producing non-market output, the 2008 SNA suggests that output may be valued in current price terms as the sum of the total costs of production. These costs include (section 6.130):
- intermediate consumption
- compensation of employees
- consumption of fixed capital
- other taxes (less subsidies) on production
This approach implies that for nominal non-market output, gross operating surplus is assumed to be equal to consumption of fixed capital (depreciation), thereby making net operating surplus equal to zero.
In the special case of units that produce both non-market and market output, the non-market output component of such units is valued in current price terms as “the difference between the total costs of production minus the revenues from market output”. Following this guidance, there is little variation between countries in the methodology used for current price estimates of non-market output.
Volume estimates
The measurement challenge is far greater when measuring output in volume terms. The typical approach for the volume measurement of market services involves the deflation of the output measure in current prices.
In practice, deflators are typically applied at industry section or sub-section level or at the level of specific types of output, such as components of Consumer Price Indices (CPIs) or Producer Price Indices (PPIs). This has the benefit of ensuring volume estimates are all in the same price base and changes in the quality of products detected through prices are captured in the volume of output. However, quantity indicators, such as those based on employment data, may also be used for measuring market output, particularly for early quarterly estimates. Additionally, quantity indicators are often used for volume estimates of trade in goods.
The measurement of non-market output differs, as there is no explicit price from which to construct a deflator. Therefore, alternative methodologies must be sought. These can be grouped into four categories:
- deflation using output prices
- deflation using input prices
- direct output indicators
- direct input indicators
The first two categories are considered “indirect” methods as the volume estimate is created “indirectly” through first estimating the current price estimate and then deflating using a chosen proxy price index. The second two categories are considered “direct” methods as the indicator is used to directly move forward the volume estimate irrespective of the current price estimate.
Deflation using output prices
Deflation using output prices is the approach most similar to the conventional approach to measuring the volume of market services. As non-market prices are non-existent, this approach involves deflating the output of non-market services using deflators constructed from price data associated with market output produced, such as components of CPI or PPI.
When applying this method, compilers should be mindful that the composition of services provided by the market and non-market sector might vary. For instance, hospital service providers in the market sector may provide a different range of elective surgery (such as cosmetic surgery and treatments with long waiting lists in the non-market sector) than non-market providers. Therefore, the output deflator calculated for the market sector may not be representative of the services provided by the non-market sector.
Similarly, growth in prices and costs for market services will be subject to market forces such as competition, whereas for non-market services cost growth will usually be influenced by budgets and government policies on efficiency. Therefore, the use of output prices is most suitable when the composition of market and non-market services are relatively similar, although even then, its use implies that the relationship between expenditure and volume is the same between the market and non-market sector.
Deflation using input prices
Deflation using input prices involves deflating the output of non-market services using deflators constructed from price data associated with the inputs used, predominantly labour inputs and intermediate consumption (goods and services consumed as inputs during production).
Using input prices may be more accurate than using output prices because of the level of disaggregation at which these prices can be applied. The limitation of this approach is that, by definition, volume output growth will be measured at the same rate as volume input growth and so this approach assumes that there is no change over time in productivity for non-market services.
Consequently, the input price approach is generally considered inferior to the direct output indicators method discussed below. However, the use of input prices to deflate output may be appropriate where the variety of services provided is too large to enable groupings for relatively homogenous activity types that can be counted using direct output indicators.
Direct output indicators
At its simplest level, use of direct output indicators involves changes in the level of output volumes. It is driven by non-monetary indicators related to the service provision in question, independently of the service expenditure1. The indicators used explicitly relate to the output, such as student numbers or medical appointments. The 2008 SNA, section 15.122 states that the use of direct output indicators is the recommended approach for non-market services where the appropriate data are available.
Where a service provides a range of outputs of varying value, weights usually need to be applied. For instance, hospital services can vary greatly in value, with a major surgical operation requiring a greater weight in assessing the volume changes of healthcare services than a brief outpatient consultation.
For non-market output, where there is an absence of economically significant prices to distinguish and weight different activities, costs may be used instead. In this regard, a common direct output indicator is the cost-weighted activity index, where growth in more costly activities has a greater effect on the quantity change in output although the overall impact is still dependent on the weight that is given to this activity. Because of this, compilers should be mindful of changes in the composition of services over time. This issue is particularly pertinent during the coronavirus pandemic, where many services, such as elective surgery, were restricted, and new services, such as COVID-19 testing, were created.
Direct input indicators
Direct input indicators also use non-monetary indicators to assess the change in output, independently from its monetary level. However, unlike those focusing on specific outputs, these indicators focus on volumes of inputs, such as staff numbers or staff hours.
As with direct output indicators, when input indicators refer to inputs of differing costs, such as employees at different pay bands, it may be appropriate to calculate a cost-weighted index by weighting staff numbers by the respective costs of different staff groups. It is important to note that the specific choice of input indicator could lead to significant differences. For example, as shown during the coronavirus pandemic, the use of employee numbers and employee hours worked are both considered direct input indicators but may produce very different results in the situation of furloughed employees.
Furloughed employees include those that are temporarily stood down from undertaking duties but are still receiving some or all of their standard pay. While payments are paid by the employer, during the coronavirus pandemic employers with furloughed workers were usually the recipient of government support schemes designed to maintain the employer-employee relationship. This includes the Kurzarbeit in Germany, the Chômage Partiel in France, Jobkeeper in Australia, the Coronavirus Job Retention Scheme (CJRS) in the UK and the temporary wage subsidy scheme in Ireland.
As with other measurement approaches focused on inputs, this approach does not allow for changes in productivity over time. Therefore, the use of output indicators is preferred.
Considerations in the choice of non-market output methodology
The choice of methodology will depend on the nature of the service provided and data availability. Chief among the differences in service provision is the distinction between those that are individually consumed, that is received by specific individuals (such as education and healthcare), and those that are collectively consumed, that is received simultaneously by a (section of) society as a whole (such as policing or national defence).
In general, the activities that define individually consumed non-market services, such as surgical procedures and school lessons, are easily identified. Where adequate data are readily available, direct output indicators are typically preferred. In contrast, identifying the discrete activities of collectively consumed non-market services and acquiring the data needed to produce a direct output indicator is often more difficult so input indicators may be needed for collectively consumed non-market services.
In practice, National Statistics Institutes (NSIs) are constrained in what methodologies they employ for non-market output by the timeliness and quality of available data. If more data becomes available over time, methods may change accordingly, improving volume estimates. This may also cause revisions, particularly when specific events affect the provision of non-market services (such as the coronavirus pandemic).
Comparability of non-market output measures
The different methodological approaches may well bring about difficulties in comparability between non-market volume output measures across countries. For instance, input-based measures may not account for productivity improvements that output indicators would capture. An example in healthcare would be a cure for which a technological improvement allowed for an increased number of treatments per day to be performed by a single doctor. If one country uses the “direct input indicators” approach and another similar country uses the “direct output indicators” approach, in the case of unchanged number of doctors, the first country would not see a change in volume estimates while in the second country, volume estimates would increase.
Methodological choices may also generate different results depending on national institutional contexts. For example, if a country’s education system allows for or incentivises part-time study, using number of students enrolled as an output indicator rather than number of students adjusted for full time equivalency may produce different results.
Index choices when compiling volume estimates
Estimates of the volumes of goods and services can either be compiled through applying a price (or unit cost) index to current price values of production or by constructing a direct volume index. Either way, weights are needed for each output category (for example, Diagnosis-Related Groups categories for healthcare)2 to reflect the relative importance of different services in the overall aggregate.
An important decision for an index is the period from which the prices used are taken, as it is this period for which the weights correspond. For quarterly measures of non-market output, most countries, including the UK, construct weights using price and quantities of the previous year to determine the volume growth between successive quarters of the current year. They apply a Laspeyres-type index. Contrasting this is a Paasche-type index where weights are based on the unit cost of the current period applied to the quantity of the previous period.
The Laspeyres-type is favoured in practice since the use of previous period weights requires minimal information from the current period, that is, just the new prices to derive price indices or the new quantities in case of volume indices. Normally, because of the relatively stable demand and composition of non-market services, the choice of the index number formula is not a major concern. However, in 2020 the composition of outputs within the healthcare industry changed significantly for many countries.
Firstly, there was a strong increase in treatments associated with COVID-19, such as testing and intensive care of respiratory related illnesses. Additionally, because of lockdowns and other restrictions the number of “non-COVID-19” health treatments, such as dentist appointments or elective surgery, was greatly reduced in comparison with the previous year.
Furthermore, depending on the categorisation system employed in a country, unit costs may have changed substantially where COVID-19 treatment is included in existing treatment categories. Because of these changes in unit costs and the composition of activity, the choice of the reference period in determining weights is likely to have had a larger effect than in previous years.
Example
The issue is best illustrated with a numerical example (Table 1). Assume that in 2019 (denoted as t-1), a hospital treats 90 knee replacements and 5 respiratory diseases, ignoring for simplicity the distinction between quarterly and annual data. Unit costs for the two types of treatment are 10 and 15, respectively.
Given the experiences in various countries, assume that the number of treatments of respiratory diseases increased significantly in 2020 (denoted as t in Table 1) as a consequence of COVID-19 (20 compared to 5 in 2019), whereas the number of an alternative treatment (knee replacements) declined to 50, down from 90. Because of the higher demand in COVID-19 treatments, the unit cost of these also increases between t-1 and t from 15 to 20.
Procedure | Time period | Cost | Quantity | Total cost | Simple cost share | Quantity growth rate | Total growth (Laspeyres index) | Total growth (Paasche index) |
---|---|---|---|---|---|---|---|---|
Knee Replacement | t-1 | 10 | 90 | 900 | 0.92 | - | - | - |
Knee Replacement | t | 10 | 50 | 500 | 0.56 | -44.40% | - | - |
Respiratory Diseases | t-1 | 15 | 5 | 75 | 0.08 | - | - | - |
Respiratory Diseases | t | 20 | 20 | 400 | 0.44 | 300.00% | - | - |
Total procedures | t | - | - | - | - | - | -17.90% | -10% |
Download this table Table 1: Example of Laspeyres and Paasche volume indices in a situation with changes in relative cost and activity
.xls .csvIn this example, the expanding production (from 5 to 20, an increase of 300%) and cost of the more expensive COVID-19 treatments combined with the contracting production (from 50 to 90, a decrease of 44.4%) of the less expensive treatments for knee replacements leads to large difference in the cost shares between the two years.
Such a large compositional change can result in non-trivial differences in aggregate growth, depending on the index methodology chosen. If the growth rates are applied to the categories based on weights calculated using cost from the previous year (a Laspeyres-type index), recorded output would be defined as:
Where c = cost, q = quantity of activity and t = the year, resulting in a calculation of:
[(50 x 10) + (20 x 15)]/ [(90 x 10) + (5 x 15)] – 1 = - 0.179
showing a decline of -17.9%. However, if costs from the current year are used to apportion the growth rates (a Paasche-type index), recorded output would be defined as:
Where again c = cost, q = quantity of activity and t = the year, resulting in a calculation of:
[(50 x 10) + (20 x 20)]/ [(90 x 10) + (5 x 20)] – 1 = - 0.1
showing a decline of -10.0%.
Neither result is necessarily correct or incorrect. The Laspeyres-type approach likely understates growth in the case where the unit cost of the faster-growing activity is increasing, as it attaches too much weight to those treatments that drop, and too little weight to those treatments that increase.
The converse holds for the Paasche-type measure that would overstate volume growth. An average of the two measures (a Fisher-type index) could be envisaged in principle but would mean losing the practical advantages offered by the Laspeyres index, which is an important reason why it is applied by so many countries. There is also a question of consistency with index numbers used in other parts of the national accounts. For example, Laspeyres is used to construct most price indices used for deflation purchases.
Overall, while there is no simple solution, and the basic (and extreme) example provided creates a larger difference that is likely observed in aggregate outputs, the experience of the impacts in 2020 and 2021 could serve as an opportunity to test empirically how consequential the choice of an index can be, even for macro-economic aggregates.
Notes for: Methods used to measure non-market output
Since volume and nominal estimates are created independently a price index can be created by dividing one by the other. This “implicit price deflator” may be compared with other more conventional price indices to quality assure the volume estimates.
DRG (Diagnosis-Related Groups) systems are used to classify treatments into medically meaningful and relatively homogenous groups. This provides a basis for applying differential cost weights to different treatments to produce a volume output measure.
5. How national statistical institutes (NSIs) measure non-market output
In 2010, the Organisation for Economic Cooperation and Development (OECD) working paper Towards Measuring the Volume Output of Education and Health Services: A Handbook provided an inventory of countries’ practices based on a survey conducted by the OECD and Eurostat. As the coronavirus (COVID-19) pandemic brought new challenges to the measurement of non-market output, Eurostat and the OECD conducted a new inventory based on a “Questionnaire on Price and Volume Measures for Collective Non-market Services, Health Services and Education Services during COVID-19”. While this Eurostat inventory is not available publicly, a general summary is available in Annex 1.
The results of these two surveys have been crucial in understanding the prevalence and nature of different non-market output methodologies. However, because of the intricate nature of compilation and the broad nature of the economy, such surveys can only collect limited information. This leaves further questions on how different methodologies have responded to the consequences of the coronavirus pandemic.
To answer these questions, the OECD and the Office for National Statistics (ONS) jointly conducted an information gathering exercise, engaging with the eight national statistical institutes (NSIs) listed previously in Section 1, on:
- their basic methodology and data sources for measuring International Standard Industrial Classification (ISIC) sections O, P and Q, and government final consumption expenditure (GFCE)
- any differences in methodology and data sources between first and final estimates
- any adjustments applied to reflect the impact of the coronavirus pandemic
- implications of the methodology used for interpreting changes in non-market output during the coronavirus pandemic
The information collected from NSIs have shown that sum-of-costs methods are used in both annual and quarterly national accounts to estimate current price output of non-market services. For volume estimates, all four methodologies described in Section 3 are used. Several countries report the use of multiple methods for components of a service category. For example, deflation of inputs may be used to measure the output of public education while deflation of outputs is used to measure the output of private education.
Differences in methodology were not a strong driver of differences in growth for combined ISIC sections O (public administration and defence), P (educational services) and Q (human health and social care services), referred to as industries OPQ, in the pre-coronavirus pandemic period. Year-on-year growth rates in countries that made heavy use of direct output measurements showed slightly higher volatility than in countries predominantly relying on deflation using input prices, but once again, these differences are small and difficult to untangle from wider economic factors.
Trilateral discussions between the OECD, the ONS and NSIs enabled a more detailed study of the practical application of the different methodologies for non-market services across countries. This section explores the themes uncovered from this work for each of the three main industries of the non-market sector.
For simplicity, countries are listed by the predominant methodology used in quarterly and annual compilation. However, each country’s level or mix of private or public involvement in the delivery of these services should be taken into consideration when analysing the results. Full results are available in Annex 1.
Public administration and defence (section O)
ISIC section O includes:
- public administration
- defence
- law enforcement
- other collective non-market services, which are overwhelmingly publicly funded and provided
As discussed in Section 3, the collective consumption aspect of most services in ISIC section O prevents the use of direct output volume measures for most services in this industry. Direct input indicators are commonly used for volume measures of section O output, typically focussing on labour inputs. Use of data on hours worked or employee numbers are both common.
Predominant methodology used in quarterly national accounts (QNA) and annual national accounts (ANA) for public administration and defence (section O)
Input price deflation is used in:
Belgium, Canada, Norway (ANA)
Direct input indicators are used in:
Australia, Austria*, Chile*, Colombia*, Czech Republic*, Denmark*, Finland*, France, Germany*, Hungary*, Ireland, Italy, Japan* (ANA), South Korea*, Latvia*, Luxembourg*, Mexico*, Netherlands*, New Zealand*, Norway (QNA), Poland*, Portugal*, Slovak Republic*, Slovenia*, Spain*, Sweden*, South Africa*, United Kingdom, United States.
An asterisk (*) refers to the assumed approach for output of collective non-market services, such as national defence or fire services. Although most of section O consists of these types of services, some aspects are not considered as collectively consumed, such as social security administration.
Output price deflation and direct output indicators are not used as the predominant methodology in any OECD country.
In a minority of countries, indirect estimation is also used for a specific components of ISIC section O, with volume output estimated by deflating output expenditure using input prices. Deflators used include industry-specific deflators derived from national accounting systems and components of producer price indices (PPIs). For instance, the UK uses industry specific deflators based on average weekly earnings extracted from national accounts to deflate output of policing and some other government services.
Although a minority, direct output volume indicators are applied rarely for non-collective non-market services. For instance, the UK measures elements of ISIC section O, including fire protection services, prisons, probation and legal aid services, using the cost-weighted activity approach with output indicators. However, a large majority of the services in ISIC section O in the UK have no suitable activity data available for the direct output methodology, and most of this industry is measured through direct input approaches.
For both direct and indirect inputs approaches, data tend to be available for initial quarterly estimates. However, for many countries, a short period of forecasting is required for producing preliminary outputs whatever the methodology used.
Education (section P)
As an individually consumed service, education output is more easily measured by direct output indicators. This is reflected in countries’ practices; the vast majority (81%) use direct output indicators. Furthermore, several countries use input-price deflation (16%) while a smaller number apply deflation of outputs (13%) or input indicators (10%). Several countries report the use of multiple methods for components of a service category. For this reason, percentages as presented in this section may not sum to 100%.
Many countries use output indicators, such as the number of pupils or students enrolled, to measure volume change in education services in annual national accounts (ANA). Cost-weighted activity is commonly used, with different weights applied, to account for differences in costs among schooling types. Alternatively, direct output volume may be captured using pupil or student hours.
Predominant methodology used in quarterly national accounts (QNA) and annual national accounts (ANA) for education (section P)
Input price deflation is used in:
Canada, Japan (ANA), South Korea, Colombia, United States
Output price deflation is not the predominant methodology in any OECD country.
Direct input indicators are used in:
Canada, Ireland, Latvia, Norway (QNA), Spain.
Direct output indicators are used in:
Australia, Austria, Belgium, Chile, Czech Republic, Denmark, Finland, France, Germany, Hungary, Ireland, Italy, Luxembourg, Mexico, Netherlands, New Zealand, Norway (ANA), Poland, Portugal, Slovak Republic, Slovenia, Sweden, South Africa, United Kingdom.
Input cost deflation and direct input indicators, including the number of teachers employed or their hours worked, are also used for education volume estimates. Often this is because the data are available more rapidly than the data for output-based measures. Combinations of approaches are also possible. For instance, Ireland uses both direct output and input indicators whereby changes in student numbers have a large contribution to the change in growth for the industry, but changes in labour inputs are also factored in.
Countries using output indicators for their annual results will typically make quarterly estimates following an annual path based on the most recent benchmark data. In some cases, the quarterly path may depend on quarterly patterns. Enrolment data are often only available annually and output is thus spread across the four quarters using a linear trend or other estimation technique.
Healthcare (section Q)
As with education, healthcare is primarily, although not always, an individually consumed service. However, while in most OECD countries education is provided as a public service, substantial variation can be seen across countries regarding the relative size of healthcare services provided by private and by public entities.
In the US, for instance, most hospitals and many health providers are private entities charging economically significant prices1. While this is reflected in their choice of predominant methodology, different methodologies are used for other components of healthcare.
Responses to the various surveys, coupled with information publicly available from NSIs and Eurostat, show that over a third of countries (35%) use input prices to deflate output to generate the volume of healthcare services.
Almost as many countries use direct output indicators (32%), while a smaller group (23%) deflates using output prices. The latter group includes countries (10%) where healthcare is predominately delivered by the private sector, so market prices are more readily available. A further 19% of countries use direct input indicators.
Predominant methodology used in quarterly national accounts (QNA) and annual national accounts (ANA) for human health and social work activities (section Q)
Input price deflation is used in:
Austria, Canada, Chile, Colombia, Czech Republic, Denmark (QNA), Poland, South Korea.
Output price deflation is used in:
Germany, Japan (ANA), Luxembourg, South Africa, United States.
Direct input indicators are used in:
Canada, Ireland, Denmark (QNA), Latvia, Mexico, New Zealand (QNA), Slovak Republic, Spain.
Direct output indicators are used in:
Australia, Belgium, Denmark (ANA), Finland, France, Hungary, Italy, Netherlands, New Zealand (ANA), Norway, Portugal, Slovenia, Sweden, United Kingdom.
In annual national accounts, many OECD countries use direct output indicators to measure most aspects of non-market healthcare output. Specifically, volume change of hospital output, which accounts for a significant portion of non-market healthcare output, is often derived on the basis of Diagnosis-Related Groups (DRGs) or something similar such as the UK’s Healthcare Resource Groups (HRGs).
As DRG data are usually only available annually, there is substantial variation in the indicators used to measure hospital output in quarterly national accounts. Initial quarterly estimates usually come from more timely but less detailed direct output indicators, including those based on projections of the annual data. For instance, Australia has access to early but less exhaustive DRG data for use in initial estimates, while the UK employs a mixture of highly aggregated indicators spanning the main components of hospitals, primary care and prescriptions.
Alternatively, countries use input prices to deflate quarterly current price estimates or use input indicators such as employment levels. The use of such data allows preliminary estimates of quarterly national accounts to be created without requiring the level of detail used for annual national accounts, such as the compositional mix or resources used.
GFCE and non-market output
While the aggregate output of ISIC industries OPQ is a major component of GFCE, these categories do not directly match each other. This is because industry-level output may cover both non-market and market output (for example, education services may mainly be provided as non-market output but may also include driving lessons provided by private entities at market prices). Additionally, not all non-market output is captured in industries OPQ. For example, some subsidised cultural services in ISIC section R are also captured in GFCE.
The market structure of all these industries varies substantially between countries. For example, the bulk of healthcare spending in countries with highly centralised public healthcare services such as Norway or the UK would be reflected in GFCE. In contrast, healthcare spending in the heavily market-based US is more likely to be part of private consumption expenditure (PCE). These differences imply that the degree of correspondence between GFCE and industries OPQ will depend on countries’ institutional arrangements.
Furthermore, as was the case for the estimates of non-market output, NSIs also use diverse methodologies to calculate volume GFCE figures. Many NSIs construct the portions of volume GFCE coming from industries OPQ with the same measures and data used to calculate the volume output of those industries. This is the case, among others, in Canada, France and the UK. Other countries, such as Australia, deflate current price GFCE estimates to create their GFCE volume figures. As such, divergences may arise between GFCE and industries OPQ, despite them reflecting conceptually similar output2.
Notes for: How national statistical institutes (NSIs) measure non-market output
It should be noted that ownership of the economic unit is less important than the prices charged for determining whether a unit is in the market sector. Many hospitals are likely owned by non-profit institutions or theoretically even by the general government. However, units charging economically significant prices are considered market producers.
While divergences may occur at the aggregate level on a quarterly basis, at a detailed level, products are balanced during the standard compilation of Supply-Use Tables, which also benchmarks annual estimates.
7. Conclusions
Because of the need to value output without the availability of explicit prices, non-market output poses a unique challenge in national accounts measurement. While all countries derive current price estimates through a sum-of-costs approach, a variety of methods are applied to derive volume estimates.
The coronavirus (COVID-19) pandemic resulted in large-scale disruption to the delivery of non-market services, particularly in Quarter 2 (Apr to June) 2020. This led to significant changes and increasing differences in measures of non-market output and government final consumption expenditure (GFCE) across Organisation for Economic Co-operation and Development (OECD) countries.
Based on current estimates, it appears some differences may relate to the severity of the COVID-19 pandemic or to the fact that the range of services included in non-market output and GFCE measures differ between countries. However, both existing methodological differences, and those resulting from changes made in response to the pandemic, have also contributed.
The effect of methodological choices on the three main industries that predominantly make up non-market output and GFCE differs for each industry:
For public administration and defence, input-based methods predominate and the effect of COVID-19 on output appears to have been minor across the countries studied, with limited changes to methods and new adjustments
For education, although methodological differences exist between countries, most use direct output indicators; as such, variances in output outside those expected as a result of the pandemic, appear to be driven mainly by the varied adjustments that national statistical institutes (NSIs) applied to account for any perceived COVID-19-related reduction resulting from remote learning
For healthcare, a wider range of regular methodologies are applied across countries with some adopting new data and adjustments to respond to pandemic effects; despite these differences, falls in healthcare output appear to generally align with the severity of the pandemic in a country
Methodological differences, including those applied temporarily, are clearly important in understanding differences between countries’ non-market output, especially between those countries that reported similar impacts from COVID-19. In almost every OECD country that primarily used direct output indicators for healthcare and education, the output of these industries fell during the first wave of the pandemic, although the scale of the fall varied depending on factors such as the application of additional methodological adjustments.
On the other hand, countries that used deflated output or direct input indicators as their basic method for non-market output often showed a smaller fall in their non-market output over the pandemic. It is important to note that in some countries GFCE and section Q output are compiled using the same data while in others, the results are based on different sets of data.
Despite these differences, looking at countries where the industry-level data are available shows that there is a clear relationship between the scale of the impact of the pandemic measured through excess mortality and the size of the fall in education and the healthcare output. This indicates some degree of comparability remains across countries, despite the differences in methodology.
This also importantly provides some reassurance that broader comparisons of gross domestic product (GDP) growth between countries are not obscured by these methodological differences. Nevertheless, the potential consequences of different non-market output methodologies should be borne in mind when looking at the quarter-on-quarter changes in GDP observed at the peak of the COVID-19 pandemic, or where there were relatively small differences in GDP growth between countries.
These methodological differences are likely to continue to affect international comparisons of non-market output, with the pandemic having lasting effects on non-market services. For instance, the productivity of healthcare is likely to be negatively affected because of the additional resources required for infection control measures, such as personal protective equipment and the isolation of COVID-19-postive patients in healthcare settings.
Direct output-based measures may decrease as a result of such changes, while input-based measures would be likely to show an increase. Likewise, input-based measures will respond to increases in inputs providing greater contingent capacity for potential future waves of infections, whereas direct output-based measures may not.
To assist international comparisons of GDP over the pandemic period and subsequent economic recovery, or any economically volatile period, it is important that NSIs publish detailed metadata explaining both their regular methods for non-market output and any adjustments or additional data sources incorporated to account for crisis-induced changes. The following are few examples of material released by NSIs over the course of 2020 which provided an important source of reference to users:
- Australia: Economic measurement during COVID-19: Selected issues in the Economic Accounts
- Canada: Recording COVID-19 measures in the national accounts
- France: Detailed methodological notes on Quarter 2 2020 (in French only)
- The UK: Coronavirus and the impact on measures of UK government education output: March 2020 to February 2021
- The US: Gross Domestic Product, Second Quarter of 2020, Technical note
With countries often using different methodologies, interpretation, transparency and analytical potential would also be aided by NSIs publishing industry-level data on a quarterly basis. This is so that the effects of methodologies, which are often industry specific, can be better understood.
Ideally, countries should continue to move to closer alignment for their standard compilation methodologies. Convergence on the use of direct output indicators for individually consumed services, as recommended by the System of National Accounts (SNA), would provide a similar starting point across countries for healthcare and education services – although whether this is possible will depend on mechanisms for delivering education and healthcare in each country as well as on data availability.
Additionally, the international statistical community should continue to discuss and refine some of the concepts around the production of non-market services, to ensure greater consistency between countries. The impact on the quantity of education being produced when students are learning remotely compared with learning in a physical classroom is a clear example where international agreement would likely benefit cross-country comparability.
This research has clearly demonstrated that there is a need for further international discussion on these issues, both conceptual and methodological, even if it requires a level of compromise. Macro-economic indicators like GFCE and GDP need to reflect the actual economy to remain correlated to other macro-economic outcomes like unemployment and prices, but the ability to confidently compare across countries is equally fundamental.
Back to table of contents8. Annex: Predominant methods by country
These are the predominant methods used to measure the compilation of output for the three International Standard Industrial Classification (ISIC) industries most commonly captured in government final consumption expenditure (GFCE): Public administration, defence and social security services (ISIC section O); Education (ISIC section P); and Human health and social work activities (ISIC section Q), by country.
Australia
Public administration
Quarterly: Direct input indicators (hours worked)
Annual: Direct input indicators (hours worked)
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Direct output indicators (Diagnosis-Related Groups (DRG) index at lower detail)
Annual: Direct output indicators (DRG index)
Austria
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Input price deflation
Annual: Input price deflation
Belgium
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Canada
Public administration
Quarterly: Direct input indicators (Compensation of Employees (CoE), measured in hours worked) and input price deflation
Annual: Direct input indicators (CoE, measured in hours worked) and input price deflation
Education
Quarterly: Direct input indicators (CoE, measured in hours worked) and input price deflation
Annual: Direct input indicators (CoE, measured in hours worked) and input price deflation
Healthcare
Quarterly: Direct input indicators (CoE, measured in hours worked) and input price deflation
Annual: Direct input indicators (CoE, measured in hours worked) and input price deflation
Chile
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Input price deflation (public), output price deflation (private)
Annual: Input price deflation (public), output price deflation (private)
Colombia
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Input price deflation (public), direct output indicators (private; number of pupils enrolled)
Annual: Input price deflation (public), direct output indicators (private; number of pupils enrolled)
Healthcare
Quarterly: Input price deflation
Annual: Input price deflation
Czechia (Czech Republic)
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Input price deflation
Annual: Input price deflation
Denmark
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students, student hours for primary)
Healthcare
Quarterly: Direct input indicators and input price deflation
Annual: Direct output indicators
Finland
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
France
Public administration
Quarterly: Direct input indicators
Annual: Direct input indicators
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Germany
Public administration
Quarterly: Direct input indicators
Annual: Direct input indicators
Education
Quarterly: Direct output indicators
Annual: Direct output indicators
Healthcare
Quarterly: Output price indicator
Annual: Output price indicator
Hungary
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Ireland
Public administration
Quarterly: Direct input indicators (number employed)
Annual: Direct input indicators (number employed)
Education
Quarterly: Direct output and direct input indicators (number of students and teachers)
Annual: Direct output and direct input indicators (number of students and teachers)
Healthcare
Quarterly: Direct input indicators
Annual: Direct input indicators (number employed in healthcare)
Italy
Public administration
Quarterly: Direct input indicators
Annual: Direct input indicators
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Japan
Public administration
Quarterly: Direct input indicators (employee compensation)
Annual: Direct input indicators (employee compensation)
Education
Quarterly: Input price deflation
Annual: Input price deflation
Healthcare
Quarterly: Output price deflation
Annual: Output price deflation
Latvia
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Input-based methods
Annual: Input-based methods
Healthcare
Quarterly: Input-based methods
Annual: Input-based methods
Luxembourg
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: [Market]
Annual: [Market]
Mexico
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Direct output indicators (public; number of students), output price deflation (private)
Annual: Direct output indicators (public; number of students), output price deflation (private)
Healthcare
Quarterly: Direct input indicators (public), output price deflation (private)
Annual: Direct input indicators (public), output price deflation (private)
The Netherlands
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: [Market]
Annual: Direct output indicators (volume index based on International Classification of Diseases (ICDs) by age and discharge numbers)
New Zealand
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Input indicators (public), output price deflation (private)
Annual: Direct output indicators (public; composite index of DRG, patient discharge and bed night data), output price deflation (private)
Norway
Public administration
Quarterly: Direct input indicators (number employed)
Annual: Input price deflation
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Poland
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Input price deflation
Annual: Input price deflation
Portugal
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Slovakia
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Input price deflation
Annual: Input price deflation
Slovenia
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
Spain
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Direct input indicators (number employed in education)
Annual: Direct input indicators (number employed in education)
Healthcare
Quarterly: Direct input indicators (number employed in healthcare)
Annual: Direct input indicators (number employed in healthcare)
Sweden
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (student hours)
Healthcare
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (DRG index)
South Africa
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Output price deflation
Annual: Output price deflation
South Korea
Public administration
Quarterly: Input-based methods
Annual: Input-based methods
Education
Quarterly: Input price deflation (public), output price deflation (private)
Annual: Input price deflation (public), output price deflation (private)
Healthcare
Quarterly: Input price deflation (public), output price deflation (private)
Annual: Input price deflation (public), output price deflation (private)
United Kingdom
Public administration
Quarterly: Input price deflation and projection of annual output indicators
Annual: Input price deflation and direct output indicators
Education
Quarterly: Projection based on annual direct output indicators
Annual: Direct output indicators (number of students)
Healthcare
Quarterly: Direct output indicators
Annual: Direct output indicators (HRG index)
United States
Public administration
Quarterly: Direct input indicators (employment)
Annual: Output price deflation
Education
Quarterly: Output price deflation
Annual: Output price deflation
Healthcare
Quarterly: Output price deflation
Annual: Output price deflation
Notes for: Annex: Predominant methods used to measure main ISIC industries
“Input-based methods” can consist of direct input indicators, input price deflation, or combinations of the two. Collective services are very often measured through direct input indicators, such as hours worked or number employed.
Iceland, Israel, and Lithuania are not incorporated into the list because of replies to the survey having absent or very limited information.