The U.S. Department of Agriculture’s $12 billion package to offset farmers losses from the imposition of tariffs American exports could end up shrinking after an agreement to update NAFTA was struck, Agriculture Secretary Sonny Perdue said. The aid package includes cash payments for farmers of soybeans, sorghum, corn, wheat, cotton, dairy and hogs. The USDA had already outlined the allocations for the first $6 billion at the end of August.Perdue said the picture has changed after the United States-Mexico-Canada Agreement (USMCA) was reached, a revamp of the NAFTA trade agreement between the three nations.