calculations on filtered lists

Hi,
My brain has gone to mush, and I cant work out how to solve what is essentially a very simple problem.

I have a table of data, that runs into several thousand lines.
So I can look at just what is relevant I'm using the autofilter facility.

What I'd like to do is then calculate the Min and Max figures from the resulting data that is displayed. This should then change when the filter is changed or removed.

Gavin.