Just found what looks like a bug with charts in Excel 2007.

In Excel 2003 I could add a text box to a chart and then assign a formula to
it, say =B30. The value in B30 would then appear in the text box. If I
insert say 5 rows and three columns above B30, the fomula would adjust and
become =E35.

When I do the same in Excel 2007, the formula for the box says as =B30

The workaround is to use range name, ie, =rangename. However, that adds
lots of extra steps. And users have to know to do and know that Excel 2007
behaves differently. No logic in the change, so it most likely is a bug.

Bob Flanagan