I believe this will return the STDEV if it is below a certain level. What
I'm looking for is to calulate the STDEV of only those values below a certain
level. For example. Let's say the dataset is 6%, 8%, 3%, 2%, 9%,-4%. And
the MAR is 5%. I want to calculate the STDEV(3%, 2%, -4%) that is, only
those values below 5% other values are excluded.

"Teethless mama" wrote:

=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?