Returns the standard deviation of a numeric expression evaluated over a set (biased).

返回在某一集合上对数值表达式求得的标准偏差(偏置填充)。

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December is also the least historically volatile month, with a standard deviation of returns of 3.17%.

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The last column in the table is also worthy of note, as it shows the standard deviation of returns.

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Sure enough, using standard deviation of the returns, the day after Election Day is significantly more volatile than a normal day by about 80% (1.99% vs. 1.14%).

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