Shares of Molson Coors Canada Inc. (TSX:TPX.A)( TSX:TPX.B ) are down 21% since June 1 as of close on September 22. Molson Coors stock is also down 27% year over year. Concerns emerged in early February after a fourth-quarter report was released that showed losses incurred after a U.S. impairment charge of $495.2 million.