>The speed is still the same. I have plenty of disk space available (200MB).

Still curious:
Do you know for how many records Branch="01"?
Did you try running your original query as those two separate queries?

If a large percentage of your records have Branch="01" (so that the intermediate table is huge), your performance hit is likely from the aggregation GROUP BY step. This is basically a brute-force sort-and-count process, so little surprise that neither VFP nor Access would be very fast.