Because we didn't have enough economic woes? A report released Thursday shows the 16-day federal government shutdown has cost the U.S. economy between $2 billion and $6 billion in economic output. And that might be the conservative estimate. The research, compiled by the Office of Management and Budget, also shows that 120,000 fewer private sector jobs were created in those two weeks, and fourth quarter real GDP has taken a .2 to .6 percent hit. Another big cost: $2 billion in back pay to furloughed federal employees for time they weren't able to work.