I realize that this theory is very controversial. I personally like to use it because it's all very symmetrical and each generation is parallel to each other. It's also very easy to remember.

SILENT GENERATION (1921-1940)

1921-1924: Silent-Leaning G.I./Silent Cusp

1925-1928: Early Silent

1929-1932: Core Silent

1933-1936: Late Silent

1937-1940: Silent-Leaning Silent/Boomer Cusp

BOOMER GENERATION (1941-1960)

1941-1944: Boomer-Leaning Silent/Boomer Cusp

1945-1948: Early Boomer

1949-1952: Core Boomer

1953-1956: Late Boomer

1957-1960: Boomer-Leaning Gen Jones

GEN X (1961-1980)

1961-1964: X-Leaning Gen Jones

1965-1968: Early Gen X

1969-1972: Core Gen X

1973-1976: Late Gen X

1977-1980: X-Leaning Xennial

MILLENNIAL (1981-2000)

1981-1984: Y-Leaning Xennial

1985-1988: Early Millennial

1989-1992: Core Millennial

1993-1996: Late Millennial

1997-2000: Y-Leaning Zillennial

GEN Z (2001-2020)

2001-2004: Z-Leaning Zillennial

2005-2008: Early Gen Z

2009-2012: Core Gen Z

2013-2016: Late Gen Z

2017-2020: Z-Leaning Zalpha

GEN ALPHA (2021-present)

2021-present: A-Leaning Zalpha