Filtering Minimum Date Field in Pivot Table

I am having trouble filtering for the minimum date value when it is in the row of a pivot table.

As a simple example, suppose you manage a team of 3 salespeople and you want to show how many of each product they sold in their starting month.

So you have:
1) Bob - Started Apr 2012
2) Mary - May 2012
3) Jim - June 2012

In the Pivot Table:
Row Label #1: Salesperson
Row Label #2: Month
Row Label #3: Product Type (Many types)
Values: Quantity Sold

So we have:

Bob

Apr

Product 1 Sold
Product 2 Sold
Product 3 Sold

May

Product 1 Sold
Product 2 Sold
Product 3 Sold

Jun

Product 1 Sold
Product 2 Sold
Product 3 Sold

Mary

May

Product 1 Sold
Product 2 Sold
Product 3 Sold

Jun

Product 1 Sold
Product 2 Sold
Product 3 Sold

Jim

Jun

Product 1 Sold
Product 2 Sold
Product 3 Sold

Is there a way to filter the MINIMUM month for each salesperson within the pivot table? I am trying to get only Apr performance for Bob, May performance for Mary, and Jun performance for Jim

If not, what is the easiest way to capture it automatically?

Thank you for your time.

You get better help if you post an Excel-example of your workbook, without confidential information.
Make sure the workbook demonstrates your desired results if possible, or just highlight the cells you're trying to fix.
Use BEFORE/AFTER sheets if that helps make it clearer.