Worksheet is not calculating
 

Hi There,

I have a worksheet using the following equation several hundred times. The
worksheet is about 700 rows and pulling from 2 worksheets in the same
workbook (pulling from a range of 4,000 rows). All the calculations work
great however when I try to duplicate the same worksheet, with these
equations, when I get over 6 duplicate worksheets excel notes that the
worksheet still needs to calculate. I have tools set to automatically
recalculate. And when I press F9 it still says the sheet needs to calculate.
What is causing this? Is the repetition of the calculation too many times
too much for the file?

=ROUND(SUMPRODUCT(--(WTB!$F$460:$F$4411=$F$2),--(WTB!$I$460:$I$4411=$A454),WTB!Q$460:Q$4411)/1000,0)

Thanks for your help!