That post-title took me some time to come up with...

Here's what a want to do. I have a price list from last year in a
worksheet. I created a new price list for this year in a separate Excel
document. I would like to take last years data, lay it next to current data
and calculate the percent change in pricing on a product-by-product basis.

The "hitch" that we've added about 20 to 30 new products (out of a total of
800). Right now I have the following: Column A holds the product name from
this year; Column B to holds this year's cost; Column C holds the product
names from last year and Column D holds last year's pricing. I'd like to
sort such that A1 always equals C1 and such that any Column A data that has
no match in Column C, causes columns C and D to skip the cell in the C column
during the sort.

That's confusing and I know what I want... so here's an example I'd start
with:

2006 Prod 2006 Cost 2007 Prod 2007 Cost
ABC100 0.20 ABC100 0.19
ABC150 0.45 ABC190 0.68
ABC190 0.71 ABC200 0.39
ABC200 0.39 ABC250 0.84


NOW, Here's what I'd like after the sort:

2006 Prod 2006 Cost 2007 Prod 2007 Cost
ABC100 0.20 ABC100 0.19
ABC150 0.45
ABC190 0.71 ABC190 0.68
ABC200 0.39 ABC200 0.39
ABC250 0.88 ABC200 0.84

Thanks