When I was young, there was some question about defining Baby Boomers. For a while, the cutoff was 1960, which would include me, but not my brother. Later on, he was welcomed into the fold when the U.S. Census declared 1964 as the cutoff. My daughters, born in 1997 and 1998, assumed they were Millennials, until someone said the cutoff was 1998, which would put them in two different generations even though they are only a year apart. Now it seems that they are both a part of Generation Z, Post-Millennials, or whatever they eventually decide to call them. The Pew Research center has declared these parameters.
The Silent Generation: Born 1928-1945 (73-90 years old)
Baby Boomers: Born 1946-1964 (54-72 years old)
Generation X: Born 1965-1980 (38-53 years old)
Millennials: Born 1981-1996 (22-37 years old)
Post-Millennials: Born 1997-Present (0-21 years old)
Will that change anything? Who knows! It won't change anything about your life, except possibly your label. Read more about how the change came about at Mental Floss.