5 ms·

Aren't there 366 birthdays, not 365? Are leap-day births unpersons?

by Andrex 2y ago

paulddraper 2y ago
No but they rarely have birthdays
- upon_drumhead 2y ago
  If we're going off of rarity, December 25 has 6,574 average yearly births and September 9 has almost double at 12,301 average yearly births. Taking a look at Feb 29th, it has 10467 average yearly births (for years that have a Feb 29th). So what is the level of rarity that makes a day not worth calculating? https://github.com/fivethirtyeight/data/blob/master/births/US_births_2000-2014_SSA.csv https://github.com/fivethirtyeight/data/blob/master/births/U...
  - paulddraper 2y ago
    > it has 10467 average yearly births (for years that have a Feb 29th) do you see it?
    - hnbad 2y ago
      To spell it out: leap years happen less than every four years, so the average birth rate over four years is actually closer to 2,616 - quite outside the range of 6,574 - 12,301.
wrs 2y ago
“I will leave out extra material from the original including […] accounting for leap years”
illusive4080 2y ago
I wonder if most celebrate March 1 or February 28 most of the time? March 1 is more accurate time-wise but February 28 keeps within the same month.
- paulddraper 2y ago
  Most do March 1. That comports withs the legal recognition of age. But some will do Feb out of consistency of month.
  - deleted 2y ago
    [deleted]
  - hnbad 2y ago
    Some cultures (not the US apparently) consider wishing an early birthday bad luck so I'd expect them never to celebrate on Feb 28. I know this is a thing in Central Europe, not sure how common it is. It was a big culture clash in a company I know when they moved HQ from Germany to the US because the Germans would get offended by Americans wishing them happy birthday when their birthdays were on the weekend or a bank holiday.
brudgers 2y ago
The Islamic calendar has 354 or 355 days. https://en.wikipedia.org/wiki/Islamic_calendar https://en.wikipedia.org/wiki/Islamic_calendar File under "Falsehoods programmers believe about time."
- ronsor 2y ago
  There are approximately 365¼ days in a standard solar year.

Aren't there 366 birthdays, not 365? Are leap-day births unpersons?

by Andrex 2y ago

Aren't there 366 birthdays, not 365? Are leap-day births unpersons?

paulddraper 2y ago

No but they rarely have birthdays

upon_drumhead 2y ago
If we're going off of rarity, December 25 has 6,574 average yearly births and September 9 has almost double at 12,301 average yearly births. Taking a look at Feb 29th, it has 10467 average yearly births (for years that have a Feb 29th). So what is the level of rarity that makes a day not worth calculating? https://github.com/fivethirtyeight/data/blob/master/births/US_births_2000-2014_SSA.csv https://github.com/fivethirtyeight/data/blob/master/births/U...
- paulddraper 2y ago
  > it has 10467 average yearly births (for years that have a Feb 29th) do you see it?
  - hnbad 2y ago
    To spell it out: leap years happen less than every four years, so the average birth rate over four years is actually closer to 2,616 - quite outside the range of 6,574 - 12,301.

wrs 2y ago

“I will leave out extra material from the original including […] accounting for leap years”

illusive4080 2y ago

I wonder if most celebrate March 1 or February 28 most of the time? March 1 is more accurate time-wise but February 28 keeps within the same month.

paulddraper 2y ago
Most do March 1. That comports withs the legal recognition of age. But some will do Feb out of consistency of month.
- deleted 2y ago
  [deleted]
- hnbad 2y ago
  Some cultures (not the US apparently) consider wishing an early birthday bad luck so I'd expect them never to celebrate on Feb 28. I know this is a thing in Central Europe, not sure how common it is. It was a big culture clash in a company I know when they moved HQ from Germany to the US because the Germans would get offended by Americans wishing them happy birthday when their birthdays were on the weekend or a bank holiday.

brudgers 2y ago

The Islamic calendar has 354 or 355 days. https://en.wikipedia.org/wiki/Islamic_calendar https://en.wikipedia.org/wiki/Islamic_calendar File under "Falsehoods programmers believe about time."

ronsor 2y ago
There are approximately 365¼ days in a standard solar year.