问题如下：
Initially, Fund TMT held active positions in two realestate stocks—one was over-weighted by 1 %, and the other was under-weighted by 1%. Fund TMT traded back to benchmark weights on those two stocks. Then, TMT selected two different stocks that were held at benchmark weights, one automobile stock and one technology stock. TMT over-weighted the automobile stock by 1% and underweighted the technology stock by 1%. What was the effect of TMT’s two trades on its active share? TMT’s active share:
选项：
A.decreased.
B.remained unchanged.
C.increased.
解释：
B is correct.
考点：Active Share and Active Risk
解析：只有当投资组合的主动权重绝对值的总和发生变化时，主动份额才会发生变化。在TMT基金的两笔交易中，初始头寸和新头寸都涉及两只股票，一只减持1%，另一只增持1%，因此主动权重绝对值的总和没有变化，所以主动份额并没有改变。
老师您好，
这道题干描述了3个状态，
状态1：两个相同行业的股票比benchmark一个+1%一个-1%； AS=1%
状态2：trade back to benchmark weight； As=0
状态3：两个不同行业的票比benchmark一个+1%一个-1%；AS=1%
为什么最后问的不是状态3比状态2的active share变化多少，而要用状态3去比状态1啊？那题目里面说状态2有啥意义啊？
