U.S. stocks are drifting in mixed trading as they near the end of another roller-coaster week. The S&P 500 edged down by 0.1% Friday, as nearly three out of every four stocks were falling within the index.

Wall Street's main indexes opened lower on Friday as investors sifted through conflicting comments from U.S. President Donald Trump and Beijing on developments in the U.S.-China trade war. The Dow Jones Industrial Average fell 47.