The best you can do sharing among yourselves is sharing your own risk, the risk of your own community; but your own community goes up and down and you're not sharing widely enough.

你们所能做的仅仅是在成员之间,分摊自己的风险，即你们这个小团体的风险;,但由于共有背景下的正相关性,你们的风险无法摊薄。

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