Wall Street decreased on Tuesday trading session before the U.S. government long-term foreign debt was place under negative watch and as investors weighed on continued debt limit debate showing no progress. The benchmark Dow Jones industrial average dropped 0.87% to 15,168.01, the Standard & Poor's 500 Index fell 0.71% to 1,698.06 and the Nasdaq Composite index slipped 0.56% to 3,794.01.