How to auto calculate values every month or using no. of days?

[ThinhDinh]

Info on how to calculate a month’s number of days.

Fun with Dates

Jean-Claude does not stop here hehe. Darren’s idea made me think about a formula to derive the current month’s number of days. [image] And here we go! Tested some timestamps. N+31-(FLOOR(DAY(N)/16))*15+1-DAY(N+31-(FLOOR(DAY(N)/16))*15) - (N+1-DAY(N)) Edit: Realized a bug with 28 is that when you start with dates like 1, 2 in a 31-day month then it does not convert. Back to the drawing board. Edit 2: Derived a way to add 16 days when it’s “day 16 or more”, and 31 days when it’s “less than …