Can you add percentage (%) columns to a pivot table?

[New Daddy]

I've done a fair amount of Google search and decided that there is no easy way to pull this off. But I wanted to see if people have really good tricks.

Is there an easy way to add percentage columns to a pivot table? What I want to see is the proportion of each column as percentage of the total that appears in the last column. We see this all the time in scientific data, but I'm curious that Excel provides no automatic way of doing this.

[New Daddy]

I will add that I use Excel 2003. I've looked through some tutorial videos on Youtube, and some teach you how to add percentage columns to the pivot table easily by using "calculated fields", but it looks like the percentage of row/column total was introduced only in Excel 2007.

So any trick in Excel 2003?

[New Daddy]

I've decided that there is really no easy way to do this in Excel 2003.
I've since upgraded to Excel 2007 specifically to do this. All is fine in Excel 2007.