Shoe size can tell your age
You'll need to add 1014 if your birthday's already passed this year.
Basically, it works out to:
Take your shoe size
Multiply by 100
Add 2013 (2014 for current year)
Subtract the year you were born
So Current year - year you were born = age.
Shoe size * 100 = 100 * your shoe size.
As long as you stick with the *5, +50, * 20, +1013 (or 1014) you can use any number. Shoe size, neck size, etc....
There's no use crying over spilled milk, unless it's on your keyboard.