# Favorite Mnemonics

**URL:** <https://boards.straightdope.com/t/favorite-mnemonics/197485>\
**Category:** In My Humble Opinion\
**Created:** [August 25, 2003, 9:59am UTC](https://boards.straightdope.com/t/favorite-mnemonics/197485 "2003-08-25T09:59:56Z")\
**Posts on this page:** 2\
**Page:** 4

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**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\
**Post date:** [August 27, 2003, 3:33am UTC](https://boards.straightdope.com/t/favorite-mnemonics/197485/61 "2003-08-27T03:33:03Z")

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> [@](#):
>
> All my life I have had to figure out if the year is divisible by 4 (but not 400, except in 2000) to know if it’s Leap Year.

No wonder it was rough: you have the formula wrong.

A leap year (ignoring U.S. presidential elections and summer Olympics) is any year divisible by four _except_ when it is divisible by **1** 00, in which case it must also be divisible by 400 in order to be a leap year.

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**Author:** ![Briny\_Deep](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/briny_deep/32/17188_2.png) [@Briny\_Deep](https://boards.straightdope.com/u/Briny_Deep)\
**Post date:** [August 27, 2003, 3:49am UTC](https://boards.straightdope.com/t/favorite-mnemonics/197485/62 "2003-08-27T03:49:29Z")

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Oh, right. In other words, leap years don’t occur on turn-of-the-century years, except for 1600, 2000, 2400, etc.

As a little kid I had looked forward to 2000 not being a leap year (just for the novelty of skipping a leap year) and was kind of disappointed to find out it was one of the every-four-centuries exceptions.

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