Last April the Federal Reserve said that Gross Domestic Product numbers had inched up a respectable 1.8 percent.  It was a bright spot in the midst of a bleak economy.  The White House touted the news as encouraging, and stocks went up.  Now, after a dizzying few weeks of bad news about the economy, the government has revised its numbers, saying the economy really only expanded by 0.4 percent. What happened, and what does this say about the government’s understanding of the economy? Louise Story, Wall Street and finance reporter for our partner The New York Times, joins us to help explain why the numbers were so off.