TORONTO (Bloomberg) - Canadian stocks fell for a fourth day as the US dollar neared a four-year high against the euro after Germany planned to ban certain types of bearish investments and oil dropped for a sixth straight day.

Imperial Oil Ltd., Canada's second-largest energy company, declined 1.7 percent as crude retreated to its lowest price since September. Magna International Inc., Canada's biggest auto-parts maker, lost 2.1 percent as concern that austerity measures will inhibit the European economy persisted.

The Standard & Poor's/TSX Composite Index slipped 21.07 points, or 0.2 percent, to 11,791.93 at 3:46 p.m. in Toronto. Among stocks in the index, 160 fell, 60 rallied and two were unchanged.

"What's happened in Europe gives you a cue of what kind of environment we're in," said Stephen Gauthier, who helps manage C$150 million ($145 million) as a money manager at Demers Valeurs Mobilieres in Montreal. "Suddenly, governments will have to cut spending, exactly the opposite as what you've seen in the last 12 months. Suddenly, you have an environment where you're not sure about anything."

The S&P/TSX has slumped four percent since April 26, the day before S&P cut Greece's credit rating to junk. Oil plunged 18 percent and copper futures 15 percent. Energy and raw-materials companies make up 45 percent of Canadian stocks by market value, according to data compiled by Bloomberg.

Germany's financial-services regulator said it will implement at midnight a temporary ban on naked short selling and naked credit-default swaps of government bonds of countries that use the euro.

The Canadian benchmark climbed as much as 1.2 percent today before the German announcement led to a jump in the value of the US dollar against the euro. The 11-year-old currency has tumbled 19 percent against the greenback since November 25 as European leaders have wrestled with a debt crisis.

Crude futures slumped 0.9 percent to $69.44 a barrel in New York. Exxon Mobil Corp. unit Imperial Oil decreased 1.7 percent to C$40.44. TransCanada Corp., owner of Canada's largest pipeline system, fell 1.1 percent to C$34.98.

Suncor Energy Inc., the biggest Canadian oil and gas company, gained 1.1 percent to C$31.61 after Soros Fund Management LLC disclosed a bigger stake in the company.

ShawCor Ltd., which provides products and services to the energy industry, jumped 6.5 percent to C$26.11. The company said it will lead a group of investors buying Italian pipe-coating contractor Socotherm SpA.

Industrial companies dropped the most among industries in the S&P/TSX. Canadian Pacific Railway Ltd., the country's second-largest railroad, lost 1.8 percent to C$57.53. Caterpillar dealer Finning International Inc. slumped 3.8 percent to C$17.56.

Magna declined 2.1 percent to C$73.41. The largest share of the company's revenue comes from Europe, with 39 percent originating in countries that use the euro.

Most producers of materials used in manufacturing retreated. Nickel and copper-mining company FNX Mining Co. decreased 5.4 percent to C$10.27. Quadra Mining Ltd., operator of the Robinson copper mine in Nevada, slumped five percent to C$11.80.