Crystal Reports Date syntax issue

Message

     I am having trouble with a simple record selection. I have a date field that I want to have the report show me all records where the date in this field is 45 day or older. 

In SQL I use the getdate () > -45 function, but crystal does not have it. 

So I tried to use the DateAdd with this {CrewTracking.DateCompleted} = DateAdd ("d", -45, {CrewTracking.DateCompleted}) but it is not returning any records. 

If I chage the -45 to 0 it returns all records. 

Any help here would be great.

Thanks
Jay