APPLE'S INFLUENCE: Apple's stock has been falling for weeks as investors worry that the company can't maintain the momentum on its hugely popular iPhones and iPads. On Friday Apple's stock fell more than 2 percent, dragging the Nasdaq composite index into the red.

THE HEADLINE NUMBERS: The numbers out of the government's monthly jobs report appeared encouraging at first glance. The U.S. added 146,000 jobs in November, and unemployment fell to 7.7 percent from 7.9 percent.

DIGGING DEEPER: Some analysts worried that those numbers don't tell the full story. The unemployment rate fell partly because some people gave up looking for work. The government also said the U.S. added fewer jobs in September and October than it originally estimated.