The official deflator for the U.S. Overseas Loans and Grants data is the "GDP Chain Price Index" deflator, produced annually by the Bureau of Economic Analysis (BEA) in the Department of Commerce from the National Income and Product Accounts data. The deflator is readily available and reported each year by the BEA as well as the Office of Management and Budget (OMB) in their annual Budget of the United States Government. This index is currently used by the Development Assistance Committee (DAC) of the Organization of Economic Cooperation and Development (OECD) to convert U.S. ODA flows into constant dollars.

Background: The U.S. Overseas Loans and Grants (Greenbook) website provides USAID staff and the public access to data on assistance flows from the U.S. to foreign countries. The period covered is from 1946 to the most current year available (presently 2007). The website is a valuable source for researchers interested in U.S. foreign policy and foreign assistance.

The purchasing power of the dollar changes over time primarily due to inflation. This changing value of the dollars over time makes it difficult to compare levels of assistance in different time periods. Frequent requests for “constant-dollar data” (i.e. inflation-adjusted values) prompted the inclusion of a set of queries which allow user to obtain the much desired deflated data.