# leap year?

i’m confused?

i’ve always heard that leap years were every 4 years except year that end on the 00

for example there was no leap year in 1900 but there was a leap year in 1896 and 1904

i also remember correctly answering a trivia question in 1996
“when is the next leap year?”

but i just got 2 calendars and both have february 29th

are my calendars wrong? or am i confused?

i need the help of people wiser than i!!!

has anyone else ever heard the no leap year on the 'oo rule?

Never heard that one before - My 2000 dayplanner has a 2/29/00.

She wasn’t sure what to do, so she looked at how the government did things and decided to run her life that way.

the rule for a year ending in 00 is that it must be divisible by 400 to be a leap year. So 1900 was not a leap year. 2000 is a leap year. 2100 is not, etc.

There are plenty of calendar discussions here, to get an in-depth discussion of it. But in general, yes, years divisible by 4 are leap years, except the century years, except the millenium year and it is a leap year. All comes from a balancing act of the Gregorian calendar to keep in sync with the sun.
Now, duck.

Sorry, he’s right, I hurried a little too much. Every 400 years, not every millenium.

thanks for the help folks, i got it now

And just to muddy the waters a little more, the current convention will break down sometime between the year 3000 and 4000, when we will have accumulated one extra day.

Someone has proposed that the year 4000 not not be a leap year to correct that discrepancy (to keep with the “4” conventions–every fourth year is, only every fourth century is).

We’ll see when it gets here, if there is a “we.”

It is the very fact that 2000 is a leap year that makes it the Gregorian Calendar (Pope Gregory), and not the Julian Calendar (Julius Caesar) which failed to include that very proviso.

-PIGEONMAN-
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The Legend Of PigeonMan - updates every Wed & Sat. If I can be bothered.

I once found an SD column about the rules and exceptions to the leap year. But <sarcasm>strangely</sarcasm> the archive searcher isn’t working.

It basically said:[list=1][li]a year has 365 days[/li][li]unless it’s divisible by 4, then it’s 366[/li][li]unless it’s divisible by 100, then it’s 365[/li][li]unless it’s divisible by 400, then it’s 366[/li]unless it’s divisible by 4000, then it’s 365[/list=1]

It appears that the 4000-year rule is not yet official (although tracking down an absolutely authoritative source on this vexing question is the very devil).

Actually, if things stay as they are, the 4000-year rule won’t do; it’s an undercorrection, and after 20,000 years or so, will require an extra leap year to be left out. It would have been better to make every 2000 years not a leap year, to maintain the pattern of making each individual adjustment an overcorrection, but banks, etc., really don’t want their long-term calculations messed with.

On the other hand, what with leap seconds, etc., corrections beyond the 400-year rule will probably have to be made on an ad-hoc basis, anyway.

John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams

Here is the absolutely authoritative source for Gregorian calendar:
http://personal.ecu.edu/mccartyr/inter-grav-text.html

IIRC, most countries don’t actually restate the rules of the Gregorian calendar, they just specify “Gregorian.” Thus this papal bull is still the standard (Of course this only applies to countries that use the Gregorian calendar).

I don’t think there is a later international standard. There are ISO/IEC, etc. standards for date and time formats, but none for the calendar itself.

Arjuna34

My little neice or nephew is due around the end of February, and I was wondering, since this year is a “nested exception” (number 4 on AWB’s list), how many have there previously been? No, not since the Big Bang, since the invention of the Gregorian Calendar.

If my calculations are correct, this will be the first “number 4 exception” in (British) New World. Which might make my niece/nephew a very special baby (I won’t give a durn about the little brat otherwize).

Since the Gregorian calendar was adopted in 1582, there has only been 1 year divisible by 400- the year 1600.

PS- the second link in my last post incorrectly has a period at the end, as part of the link. The correct link is: http://personal.ecu.edu/mccartyr/inter-grav.html

Arjuna34

Here’s the link to the Straight Dope Mailbag on this question: Why do we have leap years?

wots rong with mi spelin?

Actually, the New Style calendar officially used by the United Kingdom (and probably by the United States, unless there has been some overriding statute passed) is not the Gregorian Calendar.

It is merely a fortunate (harumph! harumph!) coincidence that the evil papist Gregorian Calendar gives the same results as the Good and C of E New Style calendar.

(I’m serious – the whole story is in the Britannica somewhere or other; a completely different mathematical system was worked out.)

John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams