Hi,

In a similar situation I discovered that VFP 6 (SP5) gave me an error if I tried to include a date constant, {^2500,1,1}, and had to substitute the date() function, date( 2500,1,1 ). I believe this issue has been fixed in VFP 7.

BTW, if your date substraction integer is within the range of the bintoc() function you might consider trying something like:

... + bintoc( date(2500,1,1) - Eff_Date )