In Belgium, you have National Number which is basically YYMMDD-XXX-CC where YYMMDD is the birth date XXX is the sequence number of a newborn that date or one

In Belgium, you have National Number which is basically YYMMDD-XXX-CC where YYMMDD is the birth date XXX is the sequence number of a newborn that date or one of the yet unused numbers for foreign-born CC is the mod 97 of 2YYMMDDXXX for those born over 1980 or YYMMDDXXX for the others which means that it is easy to remember and not really a secret, unlike SSN. As a side note, local bank accounts, wire transfer reference numbers, and company numbers also follow the same pattern of 9..10 digits + mod 97. Compared to the Luhn algorithm for checksums used in the rest of ther world, these are a real joy to see and use. With so much fuzz about Estonian digital state, I wonder why Belgium does not get the much deserved praise for implementing the basics just right.