The Nikkei index extended its winning streak to three trading days, closing at a fresh record high Thursday boosted by optimism about the U.S. economy after the Federal Reserve signaled three interest rate cuts for the year. The 225-issue Nikkei Stock Average ended up 812.06 points, or 2.03 percent, from Tuesday at 40,815.66. It briefly hit a record intraday high of 40,823.32.