David,

There's nothing wrong with the formula so:-

Is calculation set to manual? Tools|Options|Calculation check automatic
Is it actually a formula? Cut the formula out format cell as general and
paste it back.
Try Tools|Options|view un-check formulas.

Mike



"David" wrote:

I would be very grategul if someone could help me with a formula problem i
have.
Cell H4 has the following formula, H4
=IF(F4<"",PI()*E4/(6.5*F4),PI()*E4/G4). However it does work. What should be
happening is that if there is a value in either F4 or G4 the formula will be
calculated. But nothing happens?!!