.. It takes TOO LONG to open, save
and even locks up the computer sometimes...

Without touching anything (imo, it's best to leave all those complex
**working** formulas alone), think you could dramatically improve the
situation faced via simply setting calculation to Manual mode, with "Recalc
before save" option left *unchecked*.

In xl2003 (I don't have xl2007), the options to set the mode are available
via clicking Tools Options Calculation tab. With the manual mode setting,
you just need to press F9 only whenever recalcs are required, eg upon
completing a batch of input work. You can & should save the file frequently
as inputs proceed, w/o recalculating.
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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