I have a workbook, created by someone else, that I'm trying to clean up. The
following formula parses a long table of records:

=IF(AND(ISNUMBER(MATCH(LEFT(B612,3),'[ELR expense account
identification.xls]Sheet1'!$A$2:$A$12,0)),ISNUMBER(MATCH(C612,'[Frank''s
expense codes--GDCS and non-GDCS.xls]Sheet1'!$A$2:$A$39,0))),"Extract","")

I get the same results if ISNUMBER is removed:
=IF(AND(MATCH(LEFT(B612,3),'[ELR expense account
identification.xls]Sheet1'!$A$2:$A$12,0),MATCH(C612,'[Frank''s expense
codes--GDCS and non-GDCS.xls]Sheet1'!$A$2:$A$39,0)),"Extract","")

Any advantage to retaining ISNUMBER?

Dave
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