The SPDR S&P Retail ETF XRT.N dropped 8.3%. By Noel Randewich and Amruta Khandekar May 18 (Reuters) - Wall Street ended sharply lower on Wednesday, with Target losing around a quarter of its stock market value and highlighting worries about the U.S. economy after the retailer became the latest victim of surging prices. "We think the developing impact on retail spending as inflation outpaces wages for even longer than people might have expected is a principal factor in causing the market sell-off today," said Paul Christopher, head ofglobal marketstrategy at Wells Fargo Investment Institute.