Here's a formula that calculates how many years old Scripting News is on any given day.
double (clock.now () - date ("4/1/97")) / (60*60*24*365.25)
The answer is: 10.71110623.
It counts the number of days since its inception and divides by the number of days in a year. It accounts for leap years, assuming there is an extra 0.25 days each year.