I had considered setting up a loop with a counter to go through the original data, and using that counter to look back over the last 15 rows

That seems the simplest way to me but with 2 counters say $ix,$n. [$ix] for current position and $n counting from 1 to 15 pointing to previous row [$ix-$n] in turn. You will need to adjust the logic for the first 15 records of course.

poj

In reply to Re: Array of arrays - redux by poj
in thread Array of arrays - redux by JockoHelios

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