[Andrex]

Aren't there 366 birthdays, not 365?

Are leap-day births unpersons?

[illusive4080]

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]

Most do March 1. That comports withs the legal recognition of age.

But some will do Feb out of consistency of month.

[hnbad]

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]

The Islamic calendar has 354 or 355 days. https://en.wikipedia.org/wiki/Islamic_calendar

File under "Falsehoods programmers believe about time."

[ronsor]

There are approximately 365¼ days in a standard solar year.

[wrs]

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

[paulddraper]

No but they rarely have birthdays

[upon_drumhead]

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/U...

[paulddraper]

> it has 10467 average yearly births (for years that have a Feb 29th)

do you see it?

[hnbad]

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.