Calculation Order

  • Thread starter Thread starter Kerri
  • Start date Start date
K

Kerri

Hi

I have heard two conflicting stories:
1) Excel calculates worksheets from left to right in the
workbook.
2) Excel calculates worksheets in alphabetical order
(based on the worksheet name).

Does anyone know which is correct?

Thanks in advance for your assistance.
 
Hi Kerri,

Excel 5 and Excel 95 calculate worksheets in the order they are defined.

Excel 97 and 2000 repetitively calculate worksheets in alpahabetic name
sequence until all dependencies are resolved.

Excel2002 and 2003 still calculate worksheets in alphabetic name sequence
but use a global depency table rather than sheet dependency tables, so that
the naming of the worksheets has less effect on calculation speed.

see http://www.decisionmodels.com/calcsecretsc.htm and
http://support.microsoft.com/default.aspx?scid=kb;en-us;825012


Charles
______________________
Decision Models
FastExcel Version 2 now available.
www.DecisionModels.com/FxlV2WhatsNew.htm
 
So.... for xl2000, does this mean that calculation speed can be improved by
changing the order you place sheets or, that you name sheets depending on
dependancies to get them calculated faster.
If there is a difference, how much time are we talking about?
Rob
 
Hi Rob,

In Excel 2000, to minimise calculation time, you should name worksheets in
an alphabetic sequence that minimises forward worksheet references.

I call the amount of calc time used in iteratively calculating the
worksheets Book Overhead.
The size of the Book Overhead depends on the number and
complexity/circularity of the forward worksheet references.

In many large and poorly sequenced workbooks the Book Overhead is the most
significant factor in calculation time.

You can estimate book overhead by timing a full calculate of your workbook
and subtracting the sum of the times for a sheet calculate on each of the
worksheets.

(FastExcel analyses all this and can also optimise the worksheet calculation
sequence for you)

Charles
______________________
Decision Models
FastExcel Version 2 now available.
www.DecisionModels.com/FxlV2WhatsNew.htm
 
Thanks for that info Charles.
BTW what is the cost in Australian $ for the FastExcel?
Rob
 
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