Based on looking at generation definitions online and studying about historical events that took place, I'd surmise the idea that saeculums (set of four generations) aren’t really ~85 years but most likely around 72 years. Not to mention that the average lifespan worldwide is around 72 years or very close to it (a year or so give or take).
Finding generation equivalents based on birthyears is hard. The only ones that are probably known is GI/Silent compared to Millennials/Z and probably Boomer/X compared to Millennials/Z, making each “saeculum” 72 years instead of around ~85 years and “half-saeculum” 36 years instead of ~42.5. Based on various sources, I would say that it would be safe enough to conclude that these are the GI, Boomer, and Millennial equivalents of each other:
All/almost all sources lump them as GI/Boomers/Millennials:
1918 -> 1954 -> 1990 (Horses)
1919 -> 1955 -> 1991 (Goats)
1992 -> 1956 -> 1920 (Monkeys)
1993 -> 1957 -> 1921 (Roosters)
Some sources lump them as GI/Boomers/Millennials, and they usually/traditionally are:
1994 -> 1958 -> 1922 (Dogs)
1995 -> 1959 -> 1923 (Boars)
1996 -> 1960 -> 1924 (Mice)
Some sources lump them as GI/Boomers/Millennials, but they usually/traditionally are not:
1997 -> 1961 -> 1925 (Oxen)
1998 -> 1962 -> 1926 (Tigers)
1999 -> 1963 -> 1927 (Rabbits)
All/almost all sources don’t lump them as GI/Boomers/Millennials
2000 -> 1964 -> 1928 (Dragons)
2001 -> 1965 -> 1929 (Snakes)
2002 -> 1966 -> 1930 (Horses)
2003 -> 1967 -> 1931 (Goats)
If you look at it in a big picture, it does make a little bit of sense. It also seems to coincide with the Chinese Zodiac, as shown above.
I would also argue that the ages of each equivalent were similar to each other when certain events took place (using 1924, 1960, and 1996 - the Mice years - as an example):
1924 borns were 2/3 when the Bath School disaster (arguably the GI Gen's Columbine or Y2K) took place, 4/5 when Black Tuesday took place, 14/15 during the start of WWII, and 20/21 when WWII ended.
1960 borns were 2/3 when JFK was assassinated, 4/5 when the first US troops arrived in Vietnam as well as when Immigration Act of 1965 was passed, 14/15 when the Vietnam War ended, and 20/21 when Reagan was inaugurated along with the start of the AIDS crisis.
1996 borns were 3 when Y2K took place, 4/5 when 9/11 happened and the War on Terror commenced, 14/15 when Occupy Wall Street took place, and 20/21 when Trump was inaugurated along with the rise of the #MeToo movement.
A breakdown of each generation starting with the year 1802:
Civil War Saeculum (72 years)
1802-1819: Transcendental Generation
1820-1837: Gilded Generation
1838-1855: Bleeding Generation (grew up during Bleeding Kansas and the Civil War)
1856-1873: Progressive Gen (the main people involved in the rise of progressivism in the early 20th century – Woodrow Wilson, William Jennings Bryan, Jane Addams, and Al Smith for example – were all born sometime during this 18-year span)
Great Power Saeculum (72 years)
1874-1891: Idealists
1892-1909: Automobile Generation (grew up during the rise of the automobile)
1910-1927: GI Generation (anyone 18 and older during WWII but either are unlikely to or can't remember Franz Ferdinand's assassination)
1928-1945: Silent Generation (anyone under 18 during WWII)
Millennial Saeculum (72 years)
1946-1963: Baby Boomers (born after WWII but before JFK's assassination)
1964-1981: Gen X (anyone that wasn’t 18 yet during the MTV launch but already 18 by the time Y2K happened)
1982-1999: Millennials (anyone under 18 when Y2K took place)
2000-2017: Homelanders (anyone born after Y2K but already adults when the Apophis asteroid, probably their - along with the Neo-Prophets' - equivalent of Y2K, will come)
Post-Millennial Saeculum (72 years)
2018-2035: Neo-Prophets (any minor when the Apophis incident may happen)
2036-2053: Unnamed nomad gen
2054-2071: Unnamed hero gen
2072-2089: Unnamed artist gen
Please let me know what you think about this idea.
Finding generation equivalents based on birthyears is hard. The only ones that are probably known is GI/Silent compared to Millennials/Z and probably Boomer/X compared to Millennials/Z, making each “saeculum” 72 years instead of around ~85 years and “half-saeculum” 36 years instead of ~42.5. Based on various sources, I would say that it would be safe enough to conclude that these are the GI, Boomer, and Millennial equivalents of each other:
All/almost all sources lump them as GI/Boomers/Millennials:
1918 -> 1954 -> 1990 (Horses)
1919 -> 1955 -> 1991 (Goats)
1992 -> 1956 -> 1920 (Monkeys)
1993 -> 1957 -> 1921 (Roosters)
Some sources lump them as GI/Boomers/Millennials, and they usually/traditionally are:
1994 -> 1958 -> 1922 (Dogs)
1995 -> 1959 -> 1923 (Boars)
1996 -> 1960 -> 1924 (Mice)
Some sources lump them as GI/Boomers/Millennials, but they usually/traditionally are not:
1997 -> 1961 -> 1925 (Oxen)
1998 -> 1962 -> 1926 (Tigers)
1999 -> 1963 -> 1927 (Rabbits)
All/almost all sources don’t lump them as GI/Boomers/Millennials
2000 -> 1964 -> 1928 (Dragons)
2001 -> 1965 -> 1929 (Snakes)
2002 -> 1966 -> 1930 (Horses)
2003 -> 1967 -> 1931 (Goats)
If you look at it in a big picture, it does make a little bit of sense. It also seems to coincide with the Chinese Zodiac, as shown above.
I would also argue that the ages of each equivalent were similar to each other when certain events took place (using 1924, 1960, and 1996 - the Mice years - as an example):
1924 borns were 2/3 when the Bath School disaster (arguably the GI Gen's Columbine or Y2K) took place, 4/5 when Black Tuesday took place, 14/15 during the start of WWII, and 20/21 when WWII ended.
1960 borns were 2/3 when JFK was assassinated, 4/5 when the first US troops arrived in Vietnam as well as when Immigration Act of 1965 was passed, 14/15 when the Vietnam War ended, and 20/21 when Reagan was inaugurated along with the start of the AIDS crisis.
1996 borns were 3 when Y2K took place, 4/5 when 9/11 happened and the War on Terror commenced, 14/15 when Occupy Wall Street took place, and 20/21 when Trump was inaugurated along with the rise of the #MeToo movement.
A breakdown of each generation starting with the year 1802:
Civil War Saeculum (72 years)
1802-1819: Transcendental Generation
1820-1837: Gilded Generation
1838-1855: Bleeding Generation (grew up during Bleeding Kansas and the Civil War)
1856-1873: Progressive Gen (the main people involved in the rise of progressivism in the early 20th century – Woodrow Wilson, William Jennings Bryan, Jane Addams, and Al Smith for example – were all born sometime during this 18-year span)
Great Power Saeculum (72 years)
1874-1891: Idealists
1892-1909: Automobile Generation (grew up during the rise of the automobile)
1910-1927: GI Generation (anyone 18 and older during WWII but either are unlikely to or can't remember Franz Ferdinand's assassination)
1928-1945: Silent Generation (anyone under 18 during WWII)
Millennial Saeculum (72 years)
1946-1963: Baby Boomers (born after WWII but before JFK's assassination)
1964-1981: Gen X (anyone that wasn’t 18 yet during the MTV launch but already 18 by the time Y2K happened)
1982-1999: Millennials (anyone under 18 when Y2K took place)
2000-2017: Homelanders (anyone born after Y2K but already adults when the Apophis asteroid, probably their - along with the Neo-Prophets' - equivalent of Y2K, will come)
Post-Millennial Saeculum (72 years)
2018-2035: Neo-Prophets (any minor when the Apophis incident may happen)
2036-2053: Unnamed nomad gen
2054-2071: Unnamed hero gen
2072-2089: Unnamed artist gen
Please let me know what you think about this idea.