Hi Mark,

Your solution is good, but it has a limitation in that if a period start and end more than one hour apart, it doesn't get calculated.

Dwain: Yours, I can't really understand (my limitation), but there is something wrong, if you alter the first end time to 13:30, then it counts all the extra hours in the 10:00 slot.

Thanks for your efforts and help. I'll have to keep going until I beat it.

Matt