The Toronto Stock Exchange's  S&P/TSX fell 75.65 points, or 0.46 percent, to 16,321.75.

Leading the index were Stars Group Inc, up 14.8 percent, Cascades Inc, up 9.8 percent, and ECN Capital Corp, higher by 7.8 percent.

Lagging shares were Magna International Inc, down 10.0 percent, Cronos Group Inc, down 8.1 percent, and Nexgen Energy Ltd, lower by 5.0 percent.

On the TSX 99 issues rose and 138 fell as a 0.7-to-1 ratio favored decliners. There were 5 new highs and 8 new lows, with total volume of 222.9 million shares.

The most heavily traded shares by volume were Crescent Point Energy Corp, Encana Corp and Manulife Financial Corp.

The TSX's energy group fell 0.17 points, or 0.1 percent, while the financials sector slipped 1.64 points, or 0.5 percent.

West Texas Intermediate crude futures fell 0.84 percent, or $0.52, to $61.6 a barrel. Brent crude  fell 0.21 percent, or $0.15, to $70.22 [O/R]

The TSX is up 14 percent for the year.