Gold prices extend gains in early trading as investors turn their focus to a raft of key U.S. economic data this week for more cues on the monetary policy outlook.New York futures rose 0.6% to $4,479.90 a troy ounce, while the U.S. dollar index was flat at 98.24. Bullion climbed in the previous session as the U.S. capture of Venezuela's President Nicolas Maduro spurred haven demand."Gold is coming off its strongest annual performance since 1979, but in the near term, gold prices may face pressure from commo ...