84 years old now in 2025 - what year born?

Today, 23 January 2025 if a person is 84 years old now, what year was he born? See below:

If 84 years old, year of birth is:
1940 or 1941*

*It depends on whether he was born before or after 1 January 1941.

If now 84 years and his year of birth 1940 if he was born after 23 January 1940 until 31 december 1940 inclusively, and his year of birth is 1941 if he was born from 1 January 1941 to 23 January 1941.

Other examples:

If now 12 years, year of birth 2012 or 2013
If now 14 years, year of birth 2010 or 2011
If now 20 years, year of birth 2004 or 2005
If now 68 years, year of birth 1956 or 1957

HTML code:

BB code: