Wheat:  Net sales of 328,500 metric tons for 2019/2020 were up 16 percent from the previous week, but down 12 percent from the prior 4-week average.   Corn:  Net sales of 562,600 MT for 2019/2020, primarily for Mexico (361,100 MT, including 22,000 MT switched from unknown destinations and decreases of 2,100 MT), Japan (88,000 MT, including 37,000 MT switched from unknown destinations and decreases of 11,300 MT), Canada (44,000 MT, including decreases of 400 MT), unknown destinations (42,300 MT), and Jamaica (16,000 MT), were partially offset by reductions for Thailand (38,400 MT) and Costa Rica (300 MT).  For 2020/2021, total net sales of 2,500 MT were for Canada.  Exports of 458,300 MT were primarily to Mexic...