1 years old now in 2023 - what year born?

Today, 26 September 2023 if a person is 1 years old now, what year was he born? See below:

If 1 years old, year of birth is:
2021 or 2022*

*It depends on whether he was born before or after 1 January 2022.

If now 1 years and his year of birth 2021 if he was born after 26 September 2021 until 31 december 2021 inclusively, and his year of birth is 2022 if he was born from 1 January 2022 to 26 September 2022.

Other examples:

If now 7 years, year of birth 2015 or 2016
If now 16 years, year of birth 2006 or 2007
If now 22 years, year of birth 2000 or 2001
If now 71 years, year of birth 1951 or 1952

HTML code:

BB code: