Try the following...

F1, copied down:

=IF(E1=TRUE,IF(COUNTIF(E1:$E$100,FALSE),MATCH(0,N( OFFSET(E1:$E$100,ROW(E1
:$E$100)-MIN(ROW(E1:$E$100)),0,1)),0)-2,COUNTIF(E1:$E$100,TRUE)-1),"")

....confirmed with CONTROL+SHIFT+ENTER.

Hope this helps!

In article ,
Bill_S wrote:

Column E on my spreadsheet contains a series of values TRUE and FALSE in no
particular order (they are the results of a formula, the details of which I
won't bore anybody with.) I need a formula in column F that checks if the
corresponding cell in column E contains "TRUE" and if so, it counts the
number of "TRUE's" below it before the next occurrence "FALSE."