Taipei: The Taiwan Stock Exchange's main index opened down 89.73 points at 24,143.37 Monday, with a turnover of NT$5.61 billion (US$183.45 million).According to Focus Taiwan, the opening figures reflect market conditions as investors react to various economic indicators. The decline in the index suggests concerns among investors, impacting trading volumes at the start of the week. The turnover, measured in New Taiwan dollars and U.S. dollars, highlights the scale of trading activity as the market opens.