The March 1, 1995, Hogs and Pigs report showed a significant re,risionof iowa's December 1, 1994, breeding herd inventory figures. The breeding herd inventory was revised up 100,000 head to 1.5 million from the initial release of the December 1, 1994, inventory report. This decreased the previously calculated liquidation by one-third, with breeding herd inventory falling 12 percent from Sep1ember 1, 1994, to December 1, 1994, ralher than 18 percent. With a revision in the breeding herd of 100,000 head in Iowa, the question becomes, did the USDA estimation procedure miss the real story of the period? To answer this question, we must look at the procedure and definitions involved.