Twenty percent of U.S. pork production was exported in 2009. Prior to H1N1 trade constraints, U.S. pork and pork variety meats exports to China were valued at nearly $275 million in 2008. China was the United States' seventh largest market, accounting for six percent of U.S. pork and pork variety meat exports.
http://www.ustr.gov/about-us/press-office/press-releases/2010/march/us-and-china-agree-reopening-chinese-pork-market-us