Computing zero-centered standard deviation

[Rick_SAS]

Since you want to compute a nonstandard rolling statistic, I suspect you will have to program this statistic yourself by using the DATA step or PROC IML. For DATA step techniques, see the references in the article "Compute a moving average in SAS."

I suspect PROC IML will be easier if you know vector/matrix programming. For SAS/IML tips, see the article, "Rolling statistics in SAS/IML."