The code you posted does not compute the sample standard deviation, which is what Excel is computing. You need to make the N – 1 correction. (I.e. before taking the square root, multiply everything by N/(N–1)).

Or you can use the code I posted in my other reply in this thread (though yours, with the correction, is probably more efficient).

the lowliest monk

In reply to Re: standard deviation accuracy question by tlm
in thread standard deviation accuracy question by Anonymous Monk

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