For Crystal 8.5, and assuming that you want to measure whole years from the date of birth to current, I'd do it by formula fields:
a) First find the difference in months, @Months:
DateDiff("m", {birth.date}, currentdate)
b) Convert this to whole years @WholeYears
Truncate((@Months/12, 0)
c) Check for birthdays in the current month but ahead of the current date, to get @TrueYears
If Datepart("m", {birth.date}) = Datepart("m", currentdate)
and Datepart("d", {birth.date}) > Datepart("d", currentdate)
then @WholeYears-1
else @WholeYears
d) Test @TrueYears for age-band
If @TrueYears < 18 then "Less than 18"
else if @TrueYears < 23 then "18-22"
etc.
Madawc Williams
East Anglia, Great Britain