Taipei, Jan. 9 (CNA) The Taiwan Stock Exchange's main index opened lower Monday from its previous close, moving down 27.87 points at 7,092.64 on turnover of NT$1.958 billion (US$64.73 million). The weighted price index edged down 10.35 points or 0.14 percent to close at 7,120.51 Friday. (By Sofia Wu)