普钢板块12月9日跌2.2%，首钢股份领跌，主力资金净流出4.49亿元

Group 1 - The core viewpoint of the article indicates that the steel sector experienced a decline, with the overall index showing a slight decrease on the trading day [1] - The steel sector dropped by 2.2% compared to the previous trading day, with Shougang Corporation leading the decline [1] - The Shanghai Composite Index closed at 3909.52, down 0.37%, while the Shenzhen Component Index closed at 13277.36, down 0.39% [1] Group 2 - In terms of capital flow, the steel sector saw a net outflow of 449 million yuan from main funds, while retail investors contributed a net inflow of 337 million yuan [2] - Speculative funds recorded a net inflow of 112 million yuan into the steel sector [2] - Detailed capital flow for individual stocks in the steel sector is provided in the accompanying table [2]