Like GDP, unemployment, or the CPI, the government can easily change or modify the way it calculates data. In fact, data all the way back to 1929 could still be changed today.
On Friday, the Department of Commerce revised its numbers – but this time reporting more bad news about the economy. According to a Bloomberg article, the first 12 months of the U.S. recession saw the economy shrink more than twice as much as previously estimated.
The Commerce Department also reported today that the economy contracted from April to June 2009 at a 6.4 percent pace, the most since 1982.
More revised on the economy can be found here.