CBO’s Economic Forecasting Record: 2017 Update
Summary Measures of the Quality of Forecasts of Selected Economic Variables,
by Forecast Horizon and Forecaster
The root mean square error (RMSE) is a measure of forecasting accuracy. It will always be a positive value; the larger the value, the less accurate the forecasts.
Forecast errors are projected values minus actual values; the mean error is the average of the forecast errors. Mean error values greater than zero indicate that the forecaster overestimated the actual values, on average; negative values indicate that the forecaster underestimated the actual values, on average.
Date ranges refer to the years in which the forecasts were made.