Wall Street stocks slumped at the opening Thursday as 10-year Treasury note yields rose, while Canadian stocks retreated from an opening climb. The Dow Jones benchmark slipped 40 points in the first few minutes of trading as bond yields bounced back to 5.1 per cent from 5.04 per cent on Tuesday. Rates worries offset optimism on a number of takeover deals, include Hilton Hotels Corp. The TSX composite index is down 9 points, with the energy sector ahead but heavily-weighted financials exerting downward pressure.