Round Calculated Date to Start of month

[Leigh_123]

Hello,

I have a standard CalendarAuto table linked with my data set. I am trying to get a "previous period" card set up using the following code:

Start Previous Period = 
Dates[End Previous Period]-Dates[Days in Period]

I need to then round this start date to the begining of the month, ie if the return is 3 may, i need the return to be 1 may. Is there any way to do this? I tried using STARTOFMONTH however it does not allow me to do this as the calculation is not a column.

Thank you in advance

[vicky_ · Accepted solution]

use the EOMONTH(dateValue, -1) + 1
That EOMONTH will return the last day of the previous month, and then you can +1 to get the 1st day of the original dateValue

[Leigh_123]

Thank you, this is exactly what i was looking for! much appreciated.