Using the State weights determined in this manner, regional degree days are calculated in proportion to populations in the respective States. 1.0000 Regional divisions are weighted by the same procedure in the computation of national degree days. The previously described estimation and weighting procedure is used in computing current degree days and last year's degree days. Normal degree days for climatic divisions are modified slightly and are derived from normal degree days for stations. The comparisons against the previous year are all estimated and population weighted using this procedure.
Negative values indicate less degree days than normal.
The difference of the period total from the same period the previous year. The accumulated degree days from the beginning of the season. The difference of the accumulated total from the normal accumulated total. The difference of the accumulated total from the accumulated total of the same period the previous year. The ratio of the current degree days to the normal degree days expressed in percent.