The US government uses specific exchange rates for official foreign currency purchases. These rates, reported by disbursing officers at each post on the last working day of the previous month, are published in a quarterly report. These rates are crucial for government accounting and budgeting.
Significant deviations of 10% or more between current market rates and the published rates trigger amendments to the quarterly report. An amended rate appears as a new line item with a separate effective date. For example, an April 30th amendment would have two entries: the original March 31st rate and the April 30th amended rate, applicable for May and June transactions. Amendments also cover the introduction of new foreign currencies. This amendment process ensures the reported rates accurately reflect actual market conditions.
Certain transactions are exempt from these standard reporting rates. These exceptions include collections and refunds under international agreements, conversions between foreign currencies, sales of foreign currencies for US dollars, and transactions affecting dollar appropriations. Details about these exceptions are in the Treasury Financial Manual 2-3200, which provides comprehensive guidance on US government financial management and accounting.
For consistency, all US government agencies must use these published rates to convert foreign currency balances and transactions into US dollar equivalents. However, due to the inherent time lag, these rates aren’t suitable for valuing transactions affecting dollar appropriations. They primarily serve as a standardised reporting benchmark. Historical exchange rate data before 2001 is available on GovInfo.gov, with individual reports from 1963 and a consolidated report from 1956. This archive provides valuable historical context for currency analysis.