need help

[Krijgersss]

i need some help with some date colum. i have a enquete that will be filled on month base. 

now if someone fills the enquete in februari his answers are for the previous month so for Januari. 
i have a date colum but how do i make it that if they fill the enquete in februari it shows up as januari 

[lbendlin]

MONTH(EDATE([date],-1))

[Krijgersss]

This gives me back the numbers of the month the result is oke but i want to make it a date colum so i can place a relation with a calender table

[lbendlin · Accepted solution]

NewColumn = EDATE([date],-1)