If you go to the name manager you can link your pivot tables to the named range instead of the actual cells. You can use a formula like this to create your named range that will update the size when new data is added.
This looks at Sheet1 and the data that starts in A1. Then it creates a range that is as tall as the data in column A and as wide as the data in row 1. This way when any new information is added to the rows or the columns, the pivot table will see it when you hit refresh.
This may help as well: http://www.contextures.com/xlNames01.html
Bookmarks