1/yr
per year
Frequencyexact by definition
Per year is 1/31,557,600 hertz, using this site's Julian year of exactly 365.25 days. It is the unit of annual rates expressed as frequencies: earthquake recurrence intervals, component failure rates, radioactive decay constants for long-lived isotopes and annual exceedance probabilities in hydrology.
Watch out: An annual exceedance frequency of 0.01 per year is the "100-year event", which is a rate rather than a schedule. Two such events in consecutive years is unremarkable, and over a 30-year design life the probability of at least one is about 26%.
| 1 1/yr | 3.1688088e-08 Hz |
Solvers that use frequency