66 years old now in 2023 - what year born?

Today, 7 December 2023 if a person is 66 years old now, what year was he born? See below:

If 66 years old, year of birth is:
1956 or 1957*

*It depends on whether he was born before or after 1 January 1957.

If now 66 years and his year of birth 1956 if he was born after 7 December 1956 until 31 december 1956 inclusively, and his year of birth is 1957 if he was born from 1 January 1957 to 7 December 1957.

Other examples:

If now 10 years, year of birth 2012 or 2013
If now 17 years, year of birth 2005 or 2006
If now 18 years, year of birth 2004 or 2005
If now 81 years, year of birth 1941 or 1942

HTML code:

BB code: