Pivot Tables In A Shared Worksheet

The shared worksheet resides on a secure network drive, so I can access it from anywhere. For years, I've had my secretary cut and paste out separate reports on individual salesman booking/commission performance. I thought taking advantage of Excel's native Pivot Table features, would save an awful lot of work, and probably lessen the chance of errors. Then I discovered that Pivot tables don't work with shared workbooks.

So I tried un-sharing the file. I discovered that the Pivot tables worked fine, but that I had to
re-create them ( seven sales guys, 4 independent geographical territories) each reporting period. The Pivot tables weren't dynamically updated each time additional orders were added to the main list (entry worksheet). I was very careful in laying out a new version of the "entry worksheet", and eliminating any unecessary column and rows. My immediate thought is that for the Pivot tables to work dynamically, I have to have dynamic ranges in the entry worksheet.