I use LINEST to derive a multiple regression formula in Excel 2003.

I have to share this with a client who uses Excel 97.

While the results for the gradients (m) are the same, the coefficient of
determination (r2) in Excel 97 is lower than that given in Excel 2003. The
results are 0.87 and 0.97 respectively.

Does anyone know why the two versions give different answers? Which if any
is the more reliable calculation?

Regards