如果将猪肉生产视作一个完整的产出过程，那么先行指标是什么呢？

The important determinants of capacity in swine production are the number of sows, the number of surviving piglets produced per litter and the number of litters per sow per year.?

美国生猪产业分成两个部分。生猪养殖和猪肉加工。这是一个非常精炼的介绍。美国生猪养殖业的集中度几年前也并不高。

There were 68,300 U.S. swine producers in 2012. More than two-thirds of these producers had less than 100 hogs. Operations with 2,000 or more hogs accounted for only 13 percent of all operations but accounted for 87 percent of inventory (table 6). Over the last five years, swine production has continued its gradual trend to increasing concentration, with substantial declines in the number of producers in the two