>I did what you've told me, using another grouping (with expression ncount=30) inside the first one but why it didn't print all, for e.g if I have 4 pages, the 1st page was printed, the second was not, the third printed, and the last was not. Did I miss something ?
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My guess is that you aren't resetting the counter variable properly on page breaks. I don't know what you actually did or where you did it.