By Emily Chasan (Reuters)

U.S. stock futures slipped on Friday as investors traded cautiously before consumer sentiment data that could shed light on the outlook for interest rates.

Among companies, General Motors Corp. and American International Group Inc. weighed on Dow futures.

The University of Michigan will release its preliminary March consumer sentiment index at 9:45 a.m. (1445 GMT). Economists polled by Reuters expect a median reading of 88.0, compared with 86.7 in the final February report.

Standard & Poor's 500 futures were down 1.2 points, but above fair value, a mathematical formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract.

Dow Jones industrial average futures were down 19 points, and Nasdaq 100 futures were down 0.5 point.

Stocks have risen near five-year highs as investors concluded from economic reports that interest-rate increases may be ending. For its part, the Federal Reserve has stressed the importance of data as it decides how high rates should go to head off inflation.

"Investors are really kind of sniffing around for the Fed to stop raising rates," said Bruce Zaro, chief technical strategist at Delta Global Advisers.

"I think the consumer sentiment will probably be along the same lines as the benign inflation data from earlier this week."

But if the data come in too strong, it could lead traders to take profits after a strong week, said Angus Campbell, head of sales and market strategist at Finspreads.

GM shares fell about 4 percent before the bell on Inet after the company said late on Thursday its 2005 loss was $2 billion deeper than previously reported. Bonds of GM and its finance arm also fell after the news.

Insurer AIG posted a 72 percent drop in fourth-quarter profit, hurt by a legal settlement charge and hurricane losses. AIG shares slipped 1.4 percent before the bell on Inet.

Helping Nasdaq futures, a federal judge dismissed a lawsuit alleging that Google Inc.'s Web search systems infringe on a publisher's copyright. Google shares edged up 0.7 percent on Inet.

St. Paul Travelers Cos. may also be in focus after a Wall Street Journal report that Swiss insurer Zurich Financial Services was discussing a possible merger with the U.S. insurer.

Trading volume and volatility may be high on Friday as it marks the end of the two-day quadruple witching period - the quarterly settlement and expiration of four different types of March futures and options contracts.

Also on the economic front, the Federal Reserve will release industrial production and capacity utilization data for February at 9:15 a.m. (1415 GMT).