Markets on both sides of the border started off the week on a sour note yesterday as the loonie slumped more than a cent and dropping commodities prices sent energy stocks on a slide while investors returned to the U. S. dollar. The benchmark S&P/TSX composite index dropped 250.18 points, closing at 10394.78. The loonie closed at US88.31¢, down US1.14¢ as the U. S. dollar firmed up. Meanwhile, the price of gold fell US$13.20 to US$926.90 per ounce. The drop in the index was led by energy and financials, as investors did not respond well to news that EnCana Corp. (ECA/ TSX) had shuttered natural gas wells in Canada and the United States because the cost of the fuel was too low. "In some cases, we're getting below the lifting costs. You more or less have to shut them down," chief executive Randy Eresman said to reporters at an investment conference in Calgary. The resource-rich Venture Exchange also fared poorly, down 21.86 points to close at 1132.95 on the day. Jeff Wareham, a wealth advisor with ScotiaMcLeod, said the market losses are the result of people taking back profits from the run-up of the past three months. "The price of oil has doubled in the past few months. If you have a profitable trade, why don't you sell it?" he said. "I really believe today's market action was driven by profit-taking more than anything else." Mr. Wareham also pointed out that long bonds have been quite profitable as well, and investors are taking the opportunity to sell.