Tentative momentum among US stocks petered out on Monday, with the Dow dropping and the S&P losing ground after it neared a new all-time high. Sentiment has been cautiously positive on Wall Street in recent sessions, as traders continue to bet the US economy will bounce back from the pandemic strongly this year, despite fears of inflation that would lead to a tightening of Federal Reserve policy. "Investors continue to weigh the economic recovery optimism against persistent inflation uncertainty and the implications it could have on the Fed's timing of tapering its monthly asset purchases," analysts from investment bank Charles Schwab wrote. The benchmark Dow Jones Industrial Average lost 0.4 percent to 34,630.24, while the broad-based S&P 500 fell short of hitting a new record high, instead losing 0.1 percent to 4,226.52. But the tech-rich Nasdaq Composite Index rose 0.5 percent to 13,881.72. The ongoing buying assault directed at "meme stocks" by retail investors organized on the Reddit social network continued, with theater chain AMC Entertainment climbing 14.8 percent and retailer GameStop gaining 12.7 percent. Boeing rose 1.1 percent after announcing its MQ-25 T1 unmanned aircraft successfully refueled a plane in flight. cs/hs