how about entere the time in another cell as a time value. Then you won't
need to use timevalue

=IF(TIMEVALUE(TEXT(MAX(D2:D18),"hh:mm"))=M1,F1,E1)

where M1 holds the time value 21:30 or 24:00

I wouldn't think that changing M1 would make you lose your value.

--
Regards,
Tom Ogilvy

"Thomas Knapp" wrote in message
...
This formalu is in E1. If I change the timevalue from
say ("21:30") to ("24:00"), I loose the original data
which was sourced from F1 earlier. When I change the
timevalue, the cell goes back to zero. Is there any way
to change the timevalue without loosing the base data
sourced from F1?

=IF(TIMEVALUE(TEXT(MAX(D2:D18),"hh:mm"))=TIMEVALUE
("21:30"),F1,E1)