U.S. stocks fell in afternoon trading on Monday after data painted a mixed picture of the U.S. economy ahead of Friday’s highly anticipated employment report for December.

The Institute for Supply Management's non-manufacturing index showed the U.S. service sector slowed last month after the index came in at 53.0 in December, down from 53.9 the previous month. Economists polled by Reuters had estimated the index would rise to 54.6. A reading above 50 indicates expansion. Meanwhile, separate data revealed new orders for U.S. factory goods rebounded in November, rising 1.8 percent, the Commerce Department reported.

After the closing bell on Monday, Federal Reserve Vice Chair Janet Yellen is expected to be confirmed by the Senate as head of the Federal Reserve at 5:30 p.m. Eastern, replacing Chairman Ben Bernanke. The likely confirmation follows the Fed’s surprise announcement in December the central bank will scale back its $85 billion-a-month bond-buying program to $75 billion this month. The Federal Open Market Committee will release minutes from its December policy meeting on Wednesday.

Also on the economic calendar this week, investors will eye the unofficial kick off to fourth-quarter earnings season as aluminum producer and former Dow component Alcoa Inc. (NYSE: AA) reports results on Thursday.

“Well, I’m looking forward to earnings season starting and that’s really what I’m focused on,” said Jason Weisberg of Seaport Securities. “Janet Yellen is already built into the market. QE is built into the market. [FOMC minutes] have been pretty consistent over the last two years, no big surprises really.”

Other notable companies reporting earnings this week include Micron Technology Inc. (NASDAQ: MU), Monsanto Company (NYSE: MON), Family Dollar Stores Inc. (NYSE: FDO) and Bed Bath & Beyond Inc. (NASDAQ: BBBY).

“I’m focused on earnings and seeing how the cash has been on the sidelines for at least 2013 and how that’s going to be deployed and how quickly that’s going to be deployed," Weisberg added. "I’m going to be paying attention to money flows.”

The Dow Jones industrial average fell 1.31 points, or 0.01 percent, to 16,468.68. The S&P 500 Index was down 0.70 points, or 0.04 percent, to 1,830.74. The Nasdaq Composite fell 9.44 points, or 0.23 percent, to 4,122.41.