The Dow Jones industrial average jumped farther into record territory Tuesday after new reports of a sluggish economy heightened expectations that the Federal Reserve Board was about to lower interest rates. The Dow gained 76.23 points to close at 5,381.21. The New York Stock Exchange composite index also rose, gaining 3.08 to close at 337.28. On the Big Board, advancers led decliners 1,678 to 774, with 661 unchanged. The technology-heavy Nasdaq composite index rose 9.79 to end the day at 1,052.30. The Standard & Poor's 500 stocks rose 5.93 to 630. In London, gold closed at $404.75, down $ 0.90.