Hi Mike!
Charles Williams is the Excel performance wizard and a visit to his
site might help you:
Charles Williams
http://www.decisionmodels.com/calcsecretsj.htm
However, the way I see it is that Now() is volatile and that this
causes recalculation even if the precedents haven't changed. With a
recalculation of the volatile function cell all of the dependencies
will also recalculate.
It may well be that using an even handling subroutine might be
quicker. It might cut in every time there's a recalculation but then
so does NOW. But it would make no change if your dependencies haven't
changed and would then end.
But I stress that this hasn't been checked. It just seem that it might
be quicker.
If recalculation is getting to be a pain during construction phase, as
opposed to during user operation, you can always toggle auto and
manual re-calculation modes. Some delay in calculation is often not as
unacceptable as you might think. (Again, see Charles' comments on this
point).
--
Regards
Norman Harker MVP (Excel)
Sydney, Australia
Holidays and Observances Thursday 17th July: (e-mail address removed)
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