You should expect a slow down when using array formulas or SUMPRODUCT used in
lieu of an array formula. Each calculation requires multiple -- perhaps 100's
-- of calculations "under the hood".

On Mon, 10 Jan 2005 11:47:07 -0800, jrusso <jrusso@discussions.microsoft.com>
wrote:

>Hello,
>
> I defined some named ranges in one of my workbooks. I created another
>worsheet that uses references to these named ranges to generate counts using
>the SUMPRODUCT function. The result has been unacceptably slow performance
>in this workbook when using the autofilter to filter by a particular value in
>a particular column. I have the same problem when I manually enter a value
>or paste a value into a cell and move off the cell. The application says,
>"calculating" for about 4-5 minutes.
> Is there any way to improve this performance to an acceptable levesl?
>
>Thanks,
>John