[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.