Table 1 shows these ratios by forecast horizon, from the zero-quarter horizon for the last meeting of the quarter to the eight-quarter forecast for the first meeting of the quarter. [...] Comparing the lower panel of the Table to the upper, we see that differences in the magnitude of forecast errors for the Surplus were minor until the 3Q horizon, but then quickly rose with the forecast horizon to be more than double by 5Q. [...] The upper panel of Figure 3 compares the same forecast errors for the surplus seen in Figure 2 to those of the structural surplus HEB6.10 We see that the forecast errors for HEB6 are almost always less widely dispersed than those for the Surplus, presumably reflecting the impact of the additional business cycle uncertainty on the Surplus. [...] Results presented in the Appendix examine the sensitivity these results to the test statistic used, the sample period and the outcome measured to con- struct the forecast errors. [...] We use the four-quarter change in the fed funds rate ending in the quarter before the Greenbook forecast is made so that we are certain that the change in the fed funds rate was in the information set of the forecasters.