First, most consider the century to begin with the year "1": 1801, 1901, 2001, ...  Centuries end in the 100th year: 1801-1900, 1901-2000, 2001-2100, ...
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Someone born in 2001 will turn 17 sometime in 2018.
Someone born in 2002 will turn 16 sometime in 2018.
Someone born in 2003 will turn 15 sometime in 2018.
...
Someone to be born in 2022 hasn't been born yet.
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If you consider a child to be 1-year upon birth (as some cultures do), then you can argue the point before a judge because the laws that establish adulthood and the age of consent are based on being 0 years old at the moment of birth.
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As they say in the sports world (NFL teams not in the playoffs), "Wait til next year."

-- Modified on 1/1/2018 3:23:29 AM