[Vibgyor5]

I myself have a difference of exactly one year from my real birthdate and official one.

Why? Because in 80s/90s India, it was common to have 'official' birthdate extended with expectation that this will result in one additional year of government benefits. That logic does not make sense to me but was prevalent at the time of my parents/grandparents etc.

It irks me a bit at times, however, there is nothing I can really do about it at this point - all my records, passport etc. are based on 'official' birthdate. To avoid any confusion or misunderstanding, I quote official birthdate to friends and other people. Realistically, only people who're aware of my actual birthdate are my family.