TORONTO (Bloomberg) — Canadian stocks retreated, sending the Standard & Poor’s/TSX Composite Index to its biggest drop in five weeks, on concern that profit growth may falter and bad loans increase.Computer-related shares such as Research In Motion Ltd. slid on a drop in prices for computer memory chips. Financial shares including Toronto-Dominion Bank fell after a US Federal Reserve official said weak lending standards were behind rising mortgage defaults. The S&P/TSX dropped 100.35, or 0.8 percent, to 13,083.95 in Toronto.

The benchmark, which set five records in the past seven days, had its steepest slide since January 3. Investors locked in gains on speculation the rally cannot be sustained at its recent pace, said Fred Ketchen, director of equity trading at Scotia McLeod Inc. in Toronto.

“There was a change in sentiment — it’s a case of too much, too fast,” Ketchen said.

Commodity producers such as Barrick Gold Corp. and Suncor Energy Inc. declined even as bullion touched a six-month high and crude oil rose to the highest this year.

Micron Technologies Inc., the largest US maker of semiconductors, said a collapse in prices for chips has created a “horrible situation,” sending its shares to a 15-month low in New York.

Research In Motion, producer of the Blackberry e-mail phones, lost C$6.70 to C$157.20 and was the biggest drag on the S&P/TSX.

Nortel Networks Corp. was down 67 cents at C$33.93. North America’s biggest phone-gear maker has risen 6.5 percent this week after unveiling plans to cut 2,900 jobs as part of its push to regain profitability.

A gauge of computer-related shares dropped 2.4 percent today. It’s still the best performer this week, up 1.7 percent.

Loblaw Cos. declined for a second day after saying it will have a quarterly loss, the first in a decade. Canada’s biggest super-market chain fell C$2.14 to C$46.81, taking a two-day drop to 8.6 percent. Parent company George Weston Ltd. retreated C$3.21 at C$71.82, for a 9.1 percent drop this week.