S&P acknowledged making a US$2 trillion error in its justification for downgrading the credit rating of the United States in 2011, but stated that it "had no impact on the rating decision". Jonathan Portes, director of NIESR, Britain's longest established independent economic research institute, has observed that "S&P's record . . . is remarkable. The agency downgraded Japan's credit rating in 2002, since when it has had the lowest long-term interest rates in recorded economic history." Paul Krugman wrote, "it’s hard to think of anyone less qualified to pass judgment on America than the rating agencies," and, "S&P’s demands suggest that it’s talking nonsense about the US fiscal situation".