Just to clarify, do you mean 'the Nth value in column A of all that match where column B meets the criteria' or 'the Nth value from column A, only if it meets the criteria from column B'.

I'm guessing the former as that makes more sense. If that is right, here is a really messy way of doing it - worked out in about 5 minutes and in multiple columns so it can easily be followed - I'll leave it up to someone else to simplify into one column.

Column C formula: =IF(B2=**value,TRUE,FALSE)**

Column D formula: =IF(C2=TRUE,COUNTIF(INDIRECT("C2:C"&ROW()),"=true"),0)

Column E formula: =MOD(D2,Nth)

Column F formula: =IF(D2<>0,IF(E2=0,A2,""),"")

Where the 2 in the above formulas is the row.

As I say, 5 minutes work so not pretty.

Tim