Hi Mike,
I'm using TMR1 to measure the execution time of the routine. I just moved the starting and stopping of the timer so it's around the inner FOR-NEXT loop. In other words the timer is started before the inner FOR and stopped after the inner NEXT effectively excluding the array handling of the outer FOR-NEXT loop from the timing.

This time I got 1533 cycles.

So, as far as I can see it is the inner loop that is eating away the time and I still don't understand why. I'll try a DO-WHILE construct instead of the FOR-NEXT and see what I'll get.

Thanks!
/Henrik.