A helper column is a column you add to existing data that is not useful in any way except to allow some reporting to occur...it's not part of the original "actual" data.

By adding in that "helper column" of formulas, you create a series of numbers that allows you to something hard in an easy way. In this instance, the hard thing is "find the lowest time for each time". The rows with "0" in the helper column are the lowest, so you can copy all those rows, or delete all the others.

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If that takes care of your need, be sure to EDIT your original post, click Go Advanced and mark the PREFIX box [SOLVED].


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