Steve,

Not too sure the exact details of what you want, but try

=IF(L6775,(I67(L67),I67-(L67),0),0)


--

HTH

Bob Phillips
... looking out across Poole Harbour to the Purbecks
(remove nothere from the email address if mailing direct)

"Steve Lenaghan" wrote in message
...
1- I use a formula =IF(L6775,L67-75,0) to calculate extra billing
charges
in excess of 75 units. This works fine.

2- I have a second formula =IF(I67(L67),I67-(L67),0) to calculate
charges,
at a different rate, above the result of the first formula. This formula
works fine if the result of formula 1 is 0, however if the result of
formula 1 is 0 I get an undesirable figure. I've been playing with the
formula but I haven't done this in 15 years and am lost.

I have a attached a stripped version of sheet

TIA

Steve L.