美国生猪价格披露的一些问题。我们知道，USDA的一个关键价格数据是现货的协议价格，即零买零卖价格，这是构成CME指数的最重要部分。而在现货价格中，爱荷华州和明尼苏达州的价格是最有参考性。但是美国的现货价格披露制度又允许养殖场出于商业机密可以选择一定的时间不披露现货价格，如果样本太少，那么USDA就不会披露这两个主产区的现货价格，从而导致CME计算用的USDA200文件代表性不足。

现货议价样本不足的根本原因是目前猪肉市场也大量采用长单模式，很多合同都是按月或者按年的长单，从而导致现货市场的交易参与不足。

考虑到中国买入猪肉的数据是可以滞后两个月披露，所以，最近的现货价格上涨也许有这个因素。至于为什么没有在USDA出口报告中体现，同样有可能是滞后披露制度。

Murky Hog Market Leaves U.S. Farms in Dark Just as Pork Heats Up

Patchy price reporting by USDA?is sowing producer uncertainty

Volatility in hog futures reached highest in more than a year

By?Michael Hirtzer?and?Lydia Mulvany

(Bloomberg) –?

Just as the spread of African swine fever in China ignites global protein markets, it’s getting harder to find out how much hogs should cost in the U.S. Midwest.

Vertical integration in the industry has made long-term supply agreements between producers and packers more prevalent. That means fewer animals are sold in daily negotiations. On some days, negotiated purchases make up only about 1% of total trades in the U.S., Steve Meyer, economist at animal agriculture consulting firm Kerns & Associates in Ames, Iowa, said by telephone.

A sleepy spot market threatens?transparency?at a time when swine-fever disruptions are driving up volatility in Chicago hog futures. Spot sales help with the pricing of other contracts and serve as the basis for hedging risk, said Jeff Diesen, chief financial officer at The Maschhoffs. The Illinois-based producer sells about 10% of its hogs on spot markets to aid transparency.

Adding to the opaqueness, key cash hog prices published by the U.S. Department of Agriculture have been few and far between this month.

A price for negotiated hog trades in the western half of the Midwest — one of the largest concentrations of pork p