通信服务板块12月31日涨0.98%，挖金客领涨，主力资金净流入3.87亿元

Group 1 - The communication services sector increased by 0.98% on December 31, with "挖金客" leading the gains [1] - The Shanghai Composite Index closed at 3968.84, up 0.09%, while the Shenzhen Component Index closed at 13525.02, down 0.58% [1] - "挖金客" saw a significant rise of 20.00%, closing at 37.80, with a trading volume of 120,600 shares [1] Group 2 - The communication services sector experienced a net inflow of 387 million yuan from institutional investors, while retail investors saw a net outflow of 25.29 million yuan [2] - "三维通信" had a net inflow of 18.8 million yuan from institutional investors, but a net outflow of 749,900 yuan from retail investors [3] - "挖金客" recorded a net inflow of 136 million yuan from institutional investors, with retail investors showing a net outflow of 62.87 million yuan [3]