I deal with these problems by setting Precision As Displayed on under Tools,
Options, Calculation. Any chance you had it on and turned it off?

--
Jim
"HydrotechChris" wrote in message
...
| The formula is
|
=IF(D467=$D$25,IF(G4670,0,G467),IF(E467+G467*B46 7*24*60*60/1000000$D$26,($D$26-E467)*1000000/(B467*24*60*60),G467))
|
| The error occurs with the first nested IF because it should enter zero
when
| G4670, but occasionally it enters -0.00000000000001061145
| --
| Hydrotechchris
|
|
| "Pete_UK" wrote:
|
| Could you post an example of one of the formulae giving rise to this
| problem?
|
| Pete
|
| On Jul 26, 7:50 pm, HydrotechChris
| wrote:
| I have recently begun to experience random problems with conditional
IF
| formulas not returning zero but a very very tiny negative number,
which
| causes wrong results in other cells which rely on a zero value from
the IF
| formula to calculate correctly. In a reservoir routing speadsheet
with say
| 2000 rows of calculations and 1000 that should be zero, two are not,
but
| tracing them can take hours expanding every cell display to 15 or more
| decimal places to find which are not zero. I have never had this
problem
| before. It started in Office XP, but today I upgraded to Office 2003
and the
| error is still there. Using ROUND everywhere is a work around but
| significantly increases the size of the spreadsheet. Does anyone know
the
| cause and solution?
| --
| Hydrotechchris
|
|
|