证券板块12月18日跌0.98%，中银证券领跌，主力资金净流出29.67亿元

Core Viewpoint - The securities sector experienced a decline of 0.98% on December 18, with Zhongyin Securities leading the drop, while the Shanghai Composite Index rose by 0.16% to close at 3876.37, and the Shenzhen Component Index fell by 1.29% to 13053.98 [1] Group 1: Market Performance - The securities sector's main stocks saw a net outflow of 2.967 billion yuan in principal funds [2] - Retail investors contributed a net inflow of 1.73 billion yuan, while speculative funds saw a net inflow of 1.237 billion yuan [2]