[AccessD] Wrong number of arguments

I am confused as to why the following field in a query returns the error
message of wrong number of arguments. The expression works fine without
the CDec. What am I doing wrong?

 

Factor_1:
CDec(IIf([SumOf3mo_rbi]=0,[Allocations]![Factor_1],[3mo_rbi]/[SumOf3mo_r
bi]))

 

Chester Kaup

Engineering Technician

Kinder Morgan CO2 Company, LLP

Office (432) 688-3797

FAX (432) 688-3799

 

 

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