This is suitably vague enough that I don't hold out too much hope for a quick
fix, but perhaps...

I have a procedure that pulls in data from Access, and does a few
calculations and a bit of formatting. Sometimes, when my computer is in a
good mood, the time to run the macro is about 8-10 seconds. Other times it
can take up to two minutes.

Calculation is always set to manual, and it doesn't make a difference if I
have several applications open or nothing but Excel. I don't understand it.
It's easy to pass on to our customer-base if the macros take 8 seconds to
run, but not if they take two minutes.

Oh, when it does take a long time, the bit that takes ages is the pulling
from Access.

If you have any ideas, I would be most grateful.

regards
Daniel