TORONTO, May 11 (Reuters) - Canada's main stock index fell on Thursday, dragged lower by financial stocks following a downgrade by Moody's on Canada's six biggest banks, and loyalty program operator Aimia Inc AIM.TO , which plunged on news Air Canada will launch its own program.
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE fell 24.95 points, or 0.16 percent, to 15,608.26. Three of the index's 10 main groups retreated.