Hi Arvi

Thanks for your response, however, based on what you wrote, we may not be on the same page. (I may have not explained it correctly).The "MEMNO" and the "TYPE" columns are what should drive the formula. The idea is to determine for each "MEMNO" how long an "E&M" line appears AFTER a "INTRAOCULAR" line. If the "E&M" line appears BEFORE the "INTRAOCULAR" line per "MEMNO",, it is an automatic "N" because it happened before the "INTRAOCULAR". I need to determine if the "E&M" lines that appear AFTER "INRAOCULAR" lines are within 90 days of the "INTRAOCULAR" line for each MEMNO. I hope that clears it up. Or did I make it even more confusing?

Thanks