HONG KONG, August 21 (Reuters) - Hong Kong shares posted a fifth-straight day of losses on Wednesday as investors remained cautious on concerns over outflows from Asian markets ahead of a China economic survey that could offer clues on the world's second-largest economy.
The Hang Seng Index closed down 0.7 percent at its lowest in more than one week at 21,817.73. The China Enterprises Index of the top Chinese listings in Hong Kong fell 0.5 percent. Both have dropped more than 3 percent in the past four days.
China's top offshore oil explorer CNOOC Ltd ended up 4.9 percent at its highest level in six months after the company posted on Tuesday a better-than-expected first-half profit and said it was on track to meet its 2013 output target.
The HSBC China "flash" manufacturing purchasing managers index (PMI) for August, the earliest indicator of manufacturing activity in the mainland for the month, is due on Thursday.