CHICAGO (Reuters) -- U.S. beef exports continue to maintain a torrid pace with USDA on Thursday reporting last week's net sales at 11,600 metric tons, down 4 percent from the prior week, but up 8 percent from the four-week average.

Also, the latest business, led by Japan and Vietnam, puts year-to-date sales at 460,300 metric tons, up 31 percent from a year ago, USDA said.

Shipments are also up from last year at 11,500 tonnes, versus 9,700 a year ago.

"Weekly beef exports (shipments) are 18 percent above last year, that increase is down a little bit from the last ...