Comparing the UK with other countries: IMF, OECD and World Bank data

The IMF, the OECD and the World Bank are international organisations that compile economic and social statistics for their member countries on harmonised definitions. The IMF covers growth, inflation and public finances, the OECD covers its 38 mostly high-income members in depth on tax, health, labour and productivity, and the World Bank publishes long-run development indicators for almost every country. Fact-checkers use them when a claim ranks the UK against other countries, because national statistics alone rarely use the same definitions across borders.

Covers: International · Release calendar

What it publishes

IMF World Economic Outlook (WEO): forecasts and historical data for GDP, inflation, unemployment, current accounts and government finances for around 190 countries, with a database published alongside the April and October reports.
IMF Fiscal Monitor: twice-yearly analysis of public debt, deficits and spending, built on the same database as the WEO.
IMF Article IV reports on the UK: the Fund's periodic review of UK economic policy, with a staff report, press release and selected issues papers.
OECD Revenue Statistics: annual tax-to-GDP ratios and tax structures for OECD countries on a common definition, back to 1965.
OECD Health Statistics: annual data on health spending, workforce, hospital beds, waiting times and outcomes for OECD countries.
OECD Economic Outlook: twice-yearly projections for OECD and G20 economies, with interim updates in between.
OECD monthly and quarterly headline indicators on GDP, inflation and unemployment for all members, released to a published calendar.
World Bank World Development Indicators: more than a thousand series on economy, population, poverty, health, education and environment, many starting in 1960.

Key datasets

IMF World Economic Outlook databases
Each WEO database edition, with country and group series from 1980 plus projections around five years ahead; covers GDP in national currency, US dollars and PPP terms, inflation, unemployment and general government finances.
Updated: Twice a year (April and October), with interim WEO Updates
IMF World Economic Outlook reports
The WEO reports and updates, including the statistical appendix and country notes explaining definitions.
Updated: April and October, with updates around January and July
IMF Fiscal Monitor
Public finance analysis and tables on general government debt, deficits, revenue and spending for advanced and emerging economies.
Updated: Twice a year
IMF United Kingdom country page
Links to the latest UK Article IV consultation, staff reports and selected issues papers. The page shows the last Article IV Executive Board consultation as 21 July 2025.
Updated: Article IV usually annual
OECD Data Explorer
The OECD's single data platform covering every OECD dataset, with filters by country, measure and period and downloads in CSV or Excel.
Updated: Continuously updated by dataset
OECD Revenue Statistics
Tax revenue as a share of GDP and by type of tax for all OECD countries since 1965. Each December edition gives final data for two years earlier and preliminary data for the previous year.
Updated: Annual (December)
OECD Health Statistics
Health expenditure and financing, health status, risk factors, resources, quality of care, pharmaceuticals and long-term care for OECD countries.
Updated: Annual (summer), with later updates
OECD Economic Outlook
Projections for growth, inflation, unemployment and public finances for OECD members and major partners, with an annex of statistical tables.
Updated: Twice a year, plus interim reports
World Bank World Development Indicators
The World Bank's main cross-country database, covering around 200 economies with annual series from 1960 on income, population, health, education, environment and more.
Updated: Several updates a year
World Bank DataBank: WDI
Query tool to build custom tables and charts from WDI by country, series and year, with Excel and CSV export.
Updated: Updated with each WDI release
World Bank GDP per capita, PPP (current international $)
A ready-made indicator page commonly used for income comparisons, with a chart, map and download for all countries.
Updated: Annual

APIs and downloads

IMF data API (SDMX)
The IMF data portal offers SDMX 2.1 and SDMX 3.0 interfaces; the interactive Swagger documentation needs a portal account to sign in. The IMF website blocks some automated requests, so test calls from a browser first.
IMF DataMapper API
Simple JSON API for the indicators shown in IMF DataMapper, including WEO series: list indicators, countries and groups, then request an indicator code such as NGDP_RPCH with country codes and an optional periods filter. No key.
OECD SDMX API
Public SDMX REST API behind the Data Explorer, returning SDMX-ML, SDMX-JSON or CSV. No key, but the OECD limits downloads per hour and blocks traffic over the limit; its API documentation sets out the current cap.
OECD API documentation
How to build OECD API queries from the Data Explorer's Developer API panel, with notes on formats and usage limits.
World Bank Indicators API
Free REST API at api.worldbank.org/v2 returning JSON or XML for any WDI series, for example /v2/country/GBR/indicator/NY.GDP.MKTP.CD?format=json. The World Bank states API keys are no longer needed.
World Bank WDI bulk download and revision history
Full WDI database as CSV or Excel zip files, plus the income classification files and a WDI revision history spreadsheet. No key.

When it publishes

The IMF publishes the World Economic Outlook and Fiscal Monitor in April and October around its Spring and Annual Meetings, with shorter WEO Updates around January and July; the WEO database is released with each full report. The OECD publishes its Economic Outlook twice a year with interim reports in between, Revenue Statistics each December and Health Statistics each summer, and lists dates for its headline statistics news releases on a release calendar. The World Bank updates World Development Indicators several times a year and records changes in a revision history file.

How to use it to check a claim

Identify the vintage. Quote the database edition (for example WEO April or October of a given year, or Revenue Statistics of a given year), because figures for the same country and year change between editions.
Decide whether the comparison should use PPP or market exchange rates. PPP adjusts for price levels and suits living standards and output volume; market exchange rates suit claims about economic size in money terms or ability to buy imports.
Check that every country in the comparison comes from the same source and edition, rather than mixing an IMF figure for one country with a national statistic for another.
For government debt or deficits, confirm the measure: international sources use general government gross debt, which differs from the UK's headline public sector net debt published by ONS and the OBR.
For tax burden claims, use OECD Revenue Statistics, which include compulsory social security contributions, and note that the latest year is preliminary for some countries.
For health spending or doctors per head, use OECD Health Statistics and check the definitions notes for the UK, since series breaks and differing coverage of long-term care affect rankings.
For forecasts, attribute them to the named organisation and edition; a forecast is a projection, not an outturn, and may be superseded by the next edition.

Common mistakes

Rankings based on GDP at market exchange rates move with currency swings, so the UK can rise or fall places without any change in its economy.
PPP conversion factors are revised when new International Comparison Program results are published, which can shift historical per-person comparisons.
OECD averages are usually unweighted averages of member countries, not totals, and membership has changed over time.
International figures for the UK often lag or differ from the latest ONS releases because they are compiled from earlier national data and then harmonised.
Projections in the WEO and Economic Outlook are not comparable with outturn data, and a forecast quoted without that label can be read as a measured result.
Different databases use different country groups, such as 'advanced economies', 'G7', 'OECD' or 'high income', which contain different countries.

Should I use PPP or market exchange rates to compare the UK with other countries?

Use purchasing power parity when comparing living standards or the volume of output, because PPP adjusts for differences in price levels between countries. Use market exchange rates when the question is about money values, such as the size of an economy in dollars or the cost of imports. The IMF, OECD and World Bank publish both, so state which one a figure uses.

Why do IMF figures for the UK differ from ONS figures?

The IMF compiles UK data from national sources and then applies international definitions, such as general government rather than public sector debt. Its databases are also fixed at a cut-off date for each edition, so recent ONS revisions may not yet appear. Checking the WEO country notes and the edition date usually explains the gap.

Do I need an API key for OECD, IMF or World Bank data?

The World Bank Indicators API and the OECD SDMX API can be used without a key, and so can the IMF DataMapper API. The OECD caps the number of downloads per hour and temporarily blocks heavier use. The IMF's newer SDMX data portal requires an account to sign in to its interactive API documentation.

Where can I find the OECD tax-to-GDP ratio for the UK?

OECD Revenue Statistics, published each December, gives tax revenue as a share of GDP for every OECD country on a common definition, including social security contributions. The full tables are in the OECD Data Explorer. The latest year is preliminary, so figures for it may change in the following edition.

Questions answered using this source

Links checked 2026-10-13. This page describes what the source publishes and gives no verdict on any claim.