The internet is a horrible place.
I was confused when I saw this on a construction drawing dimension line today:

1399 CHB

I thought it was something to do with your birth year.
( Druid, Mon 15 Jun 2009, 21:30, archived)

Don't be silly.
He was at school then.
( The Cat's Mother Not a People Person., Mon 15 Jun 2009, 21:58, archived)