Airtable – Previous Month Filter

Create a formula field in the table called “Previous Month”. We want this formula to be 1 when the date is in the previous month, and 0 otherwise. So we can use this formula:

DATETIME_FORMAT({Date}, “YYYY-MM”) = DATETIME_FORMAT(DATEADD(NOW(), “month”, -1), “YYYY-MM”)

It takes the time NOW() and subtracts one month from it using DATEADD().