Could also do it on pi approximation day (July 22), then one doesn't have to be so exact about it.
22/7 ~= 3.14
( = 3.1415929204 )
is one approximation I have read about, attributed by some, to ancient or medieval Indian or Chinese mathematicians.
https://en.wikipedia.org/wiki/Approximations_of_pi
(Yes this is worth fighting over!)