Data revisions and forecasting
The relationship between two sets of GNP data, the earliest and the first revisions, is examined. This comparison enables us to determine whether the early numbers are valuable to forecasters. The analysis uses two methods. The first is based on a technique which has been used to evaluate whether financial and economic forecasts are valuable to the users. The second approach uses time series techniques. We conclude that revisions to the 15-day estimates that occur when the 45-day numbers are released are successful and that the 15-day numbers are useful to forecasters.