Standard & Poor's has some explaining to do: As the private agency was preparing to downgrade the United States' AAA credit rating, which the country has kept pristine for 70 years, the Treasury department discovered that S&P had miscalculated the federal deficit by $2 trillion. The error led to a furious back and forth between S&P and the Obama administration Friday afternoon, staving off a downgrade. Late Friday evening, S&P was recalculating its estimate as the White House waited for news on whether the mistake would affect the downgrade.
