The OECD Economic Outlook analyses the major economic trends over the coming 2 to 3 years. It provides in-depth coverage of the main economic issues and the policy measures required to foster growth in each member country. Forthcoming developments in major non-OECD economies are also evaluated in detail. Each edition of the Outlook provides a unique resource to keep abreast of world economic developments. The OECD Economic Outlook database is a comprehensive and consistent macroeconomic database of the OECD economies, covering expenditures, foreign trade, output, labour markets, interest and exchange rates, balance of payments, and government debt. For the non-OECD regions, foreign trade and current account series are available.

The database contains annual for the projection period. Variables are defined in such a way that they are as homogenous as possible for the countries covered. Breaks in underlying series are corrected as far as possible. Sources for the historical data are publications of national statistical agencies and OECD statistical publications such as the Quarterly National Accounts, the Annual National Accounts, the Annual Labour Force Statistics and the Main Economic Indicators. The cut-off date for information used in the compilation of the projections was the 14 November 2013.

With the OECD Economic Outlook 87, new aggregation techniques have been applied to construct the OECD area (34 countries) and the OECD euro area (15 OECD countries that are also members of Euro area). The new approach aims to better handle issues arising from evolving composition of these areas and different data availability across countries. The main changes are a switch from a fixed weighting scheme to moving weighting schemes for OECD and the direct aggregation of ratios, rather than computing them as ratios of aggregated components. Consequently, a number of series expressed in levels differ from the series previously published, while others are no longer available, particularly government and labour market data. Concerning the aggregation of world trade, a new composition has been introduced, since projections are now made for the major non-OECD economies. Thus, besides OECD and the OECD euro area, the following new regions are available: Dynamic Asian Economies (Chinese Taipei, Hong Kong, Malaysia, the Philippines, Singapore, Thailand, Vietnam); Oil Producers (Azerbaijan, Kazakhstan, Turkmenistan, Brunei, Timor-Leste, Bahrain, Iran, Iraq, Kuwait, Libya, Oman, Qatar, Saudi Arabia, United Arab Emirates, Yemen, Ecuador, Trinidad and Tobago, Venezuela, Algeria, Angola, Chad, Rep. of Congo, Equatorial Guinea, Gabon, Nigeria, Sudan); with the remaining countries in a residual 'Rest of the World' group.

In the context of the OECD Economic Outllok exercise, historical data are based on national sources to take into account the more relevant indicator and structural breaks in data are often adjusted to produce smooth series with the uses of splicing and other techniques.
As a result, EO data can differ from other sources with official data including the OECD's National Accounts, Main Economic Indicators and Employment Outlook..