Market Snapshot: S&P 500 slumps nearly 1.4% in worst day since April as Nasdaq falls over 2% after Fitch lowers U.S. credit rating

U.S. stock indexes finished sharply lower on Wednesday with the benchmark S&P 500 index registering its worst day since April, as markets were rattled by a lowering of the U.S. government’s credit rating by Fitch Ratings, while bond yields rose when the Treasury boosted the size of its debt sales, though data from ADP showed that the labor market was still quite strong in July.