July 15, 2010
CBO regularly evaluates the accuracy of its economic forecasts by comparing them with the economy's actual performance and with others' forecasts. Such evaluations help guide CBO's efforts to improve the quality of its forecasts and are also intended to assist Members of Congress in their use of the agency's estimates.
Since publishing its first macroeconomic forecast in 1976, CBO has compiled a forecasting track record that is comparable in quality with that of the Administration and that of the Blue Chip consensus. In particular, the accuracy of CBO's two-year forecasts between 1982 and 2008 paralleled that of the forecasts published by the Blue Chip consensus and the Administration over the same period. The accuracy of CBO's five-year projections also generally corresponded to that of other forecasters. Comparing CBO's forecasts with those of the Blue Chip consensus suggests that when the agency's predictions of the economy's performance missed by the largest margin, those errors probably reflected difficulties shared by other forecasters in predicting turning points in the business cycle.
CBO's forecasting record provides a measure of the uncertainty underlying forecasts under normal circumstances. However, the current degree of economic dislocation exceeds that of any previous period in the past half-century, so the uncertainty inherent in current forecasts probably exceeds the historical average.