Stocks ended the week mixed, with uncertainty about next week's jobs report sidelining investors.

The S&P 500 was down 0.19%, the Dow Jones Industrial Average fell 0.34%, and the Nasdaq added 0.18%.

The February jobs report, due next Friday, is the key release of the week and the most important piece of data between now and when the Federal Reserve meets on March 15. Economists expect 215,000 jobs to have been added to U.S. nonfarm payrolls over the past month.

A stronger number could increase expectations for a March rate hike from the Federal Reserve, which boosted interest rates in December for the first time since cutting them to nearly zero during the financial crisis. The majority of analysts predict the Fed will leave them unchanged.

Crude oil pulled lower after the latest weekly read on active oil rigs fell, though at a slower-than-expected pace. Crude oil drilling rigs in the U.S. fell by 13 to 400 in the past week, according to Baker Hughes data. West Texas Intermediate crude closed 0.9% at $32.78 a barrel.

The second estimate of fourth-quarter GDP was revised up to an annual rate of 1% from 0.7%, suggesting that the U.S. economy was in better shape than expected at the end of last year. Economists had expected GDP to be revised downward, to 0.4% growth. A stronger U.S. dollar and an inventory buildup continued to hurt manufacturing, though, with exports down 2.7% and imports falling 0.6%. Consumer spending rose 2%, though, less than an originally estimated 2.2%.

For the Federal Reserve, "the upgrade in the fourth-quarter GDP growth will likely offer some encouragement, though it is unlikely to change the current bias to remain on the sidelines at the March meeting as they assess the impact of the recent global headwinds on growth," said Millan Mulraine, deputy chief U.S. macro strategist at TD Securities, which predicts the next hike will be in June.

Traders had plenty of other data to digest on Friday in a jam-packed day on the economic calendar. The U.S. trade deficit in January widened to $62.2 billion, its largest level since June, as U.S. exporters struggled to move goods amid a stronger U.S. dollar and weaker global demand.

The consumer economy benefited from colder winter weather in January and lower gas prices. Consumer spending rose 0.5% in January, higher than the 0.3% growth economists had expected. Personal income also rose 0.5%.

In earnings news, J.C. Penney (JCP) - Get Report jumped 14.7% after strong holiday sales and fewer promotions helped to boost quarterly profit. The retailer earned 39 cents a share over the quarter, nearly 10 times its profit a year earlier. Analysts had expected 23 cents a share in earnings. Sales rose 2.6% to $4 billion.

Gap (GPS) - Get Report fell 1.34% after narrowly beating analysts' profit estimates in its fourth quarter. Revenue fell 6.5% from a year earlier, in line with estimates, while same-store sales slid 7%. The retailer also announced that it had approved a $1 billion share-buyback program.

Weight Watchers (WTW) - Get Report slid 29% after reporting an unexpected loss in its fourth quarter. The weight-reduction company reported a net loss of 3 cents a share, compared with estimates for profit of 2 cents. Revenue fell 21% to $259.2 million.

Sotheby's (BID) - Get Report shares fell 6.8% after the auction house swung to a quarterly loss. The company reported a fourth-quarter loss of 17 cents a share compared to profit of $1.06 a share a year earlier. Adjusted earnings of $1.19 a share came in above estimates.

Foot Locker (FL) - Get Report was down 4.3% despite a better-than-expected quarter. The retailer reported a 7.9% increase in comparable-store sales, building on top of the 8.7% growth in the fourth quarter. Foot Locker expects comparable-store sales to rise in the mid-single digits for the rest of the year.

Kraft Heinz (KHC) - Get Report added 3.8% after swinging to a profit of 23 cents a share in its fourth quarter, compared with a loss of 4 cents a share a year earlier. The company said it's working on streamlining after completing its merger in the middle of last year.

Kraft Heinz is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio.

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