TOM BLUMER: Revisionomics: Under Obama, “unexpectedly bad” ends up being “much worse.”

From 2007 to 2010, initial reports from the Bureau of Labor Statistics (BLS) told us that the economy lost 4.201 million jobs. BLS revisions have thus far ramped up the number of jobs lost by 2.43 million. The four-year total is now 6.631 million — a stunning 58% increase. As seen above, the bureau’s revisions to the 12 months of the real recession (July 2008 through June 2009) have shot reported job losses up by almost 1.9 million, a jaw-dropping average of 158,000 per month.

They’re not done yet. Every February, BLS performs a comprehensive “benchmark revision.” The next one will affect the period from March 2010 through December 2011. Considering the results of the past four years showing average additional job losses of 415,000, the next benchmark revision seems destined to push the figures even higher.

By contrast, from 2003 to 2006, initial BLS reports told us that the economy added 5.103 million jobs. After all revisions, the four-year total rose by 1.605 million to 6.708 million — a 31% increase. The sum of all benchmark revisions during that time was a positive 675,000.

Why did the revised data largely improve (or at least decline very little) from 2003 through 2006, while decaying horribly since 2007?

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