=IF(STDEV(A1:A5)<your value,STDEV(A1:A5),"")


"TimH" wrote:

I am trying to write a formula to calculate the Sortino Ratio defined as
(Expected (Observed) Return - Minimum Acceptable Return(MAR))/Downside
Deviation. Downside Deviation is the Standard Deviation of those returns
that are < MAR. I am familiar with STDEV function and IF function. Is there
a way to embed the IF function into the STDEV function so that it calculates
the STDEV only on the values in the range below a certain level?