So make it more precise. DOB + n * 365.2421.

365.2421 is more correct.

Nasa explains:

365 +0.25 - 0.01 + 0.0025 - 0.00025 = 365.24225

https://pumas.nasa.gov/examples/how-many-days-are-year

>Omitting a leap year every 4000 years

Wait, is this right? omitting every 100 and adding every 400 should be enough.

EDIT: the 4000-year rule is just a proposal for now. So 365.2425 is correct.

None of us will live long enough to see the 4000-year rule become a problem. I don't even expect to be around for the next 100-year rule.