水泥板块1月21日跌1.1%，西部建设领跌，主力资金净流出2152.29万元

Group 1 - The cement sector experienced a decline of 1.1% on January 21, with Western Construction leading the drop [1] - The Shanghai Composite Index closed at 4116.94, up 0.08%, while the Shenzhen Component Index closed at 14255.12, up 0.7% [1] - Key stocks in the cement sector showed varied performance, with Sifang New Material rising by 0.99% and Wan Nian Qing falling by 0.37% [1] Group 2 - Western Construction saw a significant drop of 4.78%, with a trading volume of 335,700 shares and a transaction value of 202 million yuan [2] - The cement sector's main funds experienced a net outflow of 21.52 million yuan, while retail funds saw a net outflow of 14.97 million yuan [2] - Major stocks like Conch Cement had a net inflow of 83.13 million yuan from main funds, despite a net outflow from retail investors [3]