I am attempting a mail merge to customers seeking feedback
on the number of potential referrals we've made to them.  
The format of the data is similar to the following:

Company 1    Peter    Plumber    14/5/03
Company 2    Jim    Plumber    14/6/03
Company 2    Sally    Painter    15/6/03
Company 2    Sharon    Plumber    15/6/03
Company 3    Betty    Banker    14/5/03
etc           

As seen, there are potentially multiple transactions for
each "company".  What I'd like is to do a merge that
creates a letter to each company detailing the referrals
made during that month.  In the case of the data above,
there would be 3 letters created with the letter to
company 2 detailing the three referrals made.

I imagine there is some way to do this but...is this
possible?