## World Economic Outlook Database - Groups and Aggregates Information

_World Economic Outlook_

## Source details

**Canonical URL:** [World Economic Outlook Database - Groups and Aggregates Information](https://www.imf.org/en/publications/weo/weo-database/2025/april/groups-and-aggregates)

## Other formats

- [Markdown version](/en/publications/weo/weo-database/2025/april/groups-and-aggregates/index.md)
- [Structured JSON version](/en/publications/weo/weo-database/2025/april/groups-and-aggregates/index.json)
- [Bundle manifest](/en/publications/weo/weo-database/2025/april/groups-and-aggregates/bundle-manifest.json)

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### Classification of Economies
- The World Economic Outlook (WEO) divides the world into two major groups: advanced economies and emerging and developing economies.
- The classification is not based on strict criteria, economic or otherwise, and has evolved over time.
- The objective of the classification is to facilitate analysis by providing a reasonably meaningful method of organizing data.
- Some economies remain outside the classification and therefore are not included in the analysis; Cuba and the Democratic People’s Republic of Korea are cited as examples of economies that are not IMF members and therefore not monitored by the IMF.
- Last Updated: April 2025

### Aggregation Methods — General Rules
- Composite data for country groups in the WEO are either sums or weighted averages of data for individual countries.
- Arithmetically weighted averages are used for all data for the emerging market and developing economies group—except data on inflation, for which geometric averages are used.
- Unless noted otherwise, group composites are computed if 90 percent or more of the share of group weights is represented.

### Aggregation Methods — Specific Conventions
- Domestic economy indicators (growth rates or ratios): weighted by GDP valued at purchasing power parity as a share of total world or group GDP.
- Inflation:
  - For advanced economies (and subgroups): annual rates are simple percentage changes from the previous years.
  - For world inflation and inflation in emerging market and developing economies (and subgroups): annual rates are based on logarithmic differences.
- Real GDP per capita in purchasing-power-parity terms: composites are sums of individual country data after conversion to the international dollar in the years indicated.
- Euro area sector composites: unless noted otherwise, composites for all sectors for the euro area are corrected for reporting discrepancies in transactions within the area.
- Annual GDP reporting:
  - Unadjusted annual GDP data are used for the euro area and for the majority of individual countries.
  - Cyprus, Ireland, Portugal, and Spain report calendar-adjusted data.
  - For data prior to 1999, data aggregations apply 1995 European currency unit exchange rates.

### Aggregation Methods — Fiscal, Labor, and External Sector
- Fiscal data composites: sums of individual country data after conversion to US dollars at the average market exchange rates in the years indicated.
- Unemployment rates and employment growth composites: weighted by labor force as a share of group labor force.
- External sector statistics:
  - Balance of payments data: sums after conversion to US dollars at the average market exchange rates in the years indicated.
  - Debt denominated in currencies other than US dollars: sums after conversion to US dollars at end-of-year market exchange rates.
- Foreign trade volumes and prices: arithmetic averages of percent changes for individual countries weighted by the US dollar value of exports or imports as a share of total world or group exports or imports (in the preceding year).

### Practical Implications for Data Users
- Users should expect different aggregation methods depending on the statistic:
  - Sums for many levels of nominal aggregates (converted at specified exchange rates).
  - GDP-weighted PPP shares for domestic-economy ratios and growth rates.
  - Geometric vs arithmetic vs logarithmic methods for different inflation aggregates.
- Coverage rules (90 percent threshold) mean some group composites may not be computed if country coverage falls below that threshold.
- Historical aggregation of European data applies specific exchange-rate conventions for pre-1999 data (1995 ECU exchange rates) and recognizes calendar-adjusted reporting for certain countries.

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## Content in this bundle

- **April 2025 WEO Database - Country Data Documentation**
  - [April 2025 WEO Database - Country Data Documentation (Markdown version)](/-/media/files/publications/weo/weo-database/2025/april/country-information-april-2025.pdf.md){rel="alternate" type="text/markdown"}
  - [April 2025 WEO Database - Country Data Documentation (PDF)](/-/media/files/publications/weo/weo-database/2025/april/country-information-april-2025.pdf){rel="external" type="application/pdf"}
- [Historical WEO Forecasts Database (XLSX)](/-/media/files/publications/weo/weo-database/2025/april/weohistorical.xlsx){rel="external" type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"}

---

## References

- [World Economic Outlook, April 2025](https://www.imf.org/en/publications/weo/issues/2025/04/22/world-economic-outlook-april-2025)
- [World Economic Outlook Databases](https://www.imf.org/en/Publications/SPROLLs/world-economic-outlook-databases)
- [Changes to the Database](https://www.imf.org/en/publications/weo/weo-database/changes)
- [Assumptions and Data Conventions](https://www.imf.org/en/publications/weo/weo-database/assumptions-and-data-conventions)
- [Frequently Asked Questions: WEO](https://www.imf.org/en/publications/weo/frequently-asked-questions)

_Source: https://www.imf.org/en/publications/weo/weo-database/2025/april/groups-and-aggregates_