I see what you have done here and I'm quite impressed: Search for the word
in the array and returns a true or false depending on whether an error comes
from the MATCH and ISERROR statements. Using the AND function, if both
return errors then the sum formula is not run and if 1 ISERROR/MATCH
statement is true then the sum formula is run.

Its probably the longest set of functions I've ever set out. I think when
I'm done, the worksheet will be a hefty size. I might want to think about
cutting the worksheets into workbooks in the same folder. I presume it will
be a case of changing the formula to linking to the physical location of the
workbook instead of the worksheet.

Thanks for all your help