Measure for Current Month

Hi bhmiller89,

In this scenario, you don't need to populate a date table. And I have created a simple sample about how to create the calculate column which indicates if the "create Date" is within current month for your reference.

I assume you have a table called "Table1" like below.

Then you should be able to use the formula below to create the calculate column, and use the created column as Slicer to show only Opportunities created in the current month.

IsCurrentMonth = 
    IF (
        YEAR ( Table1[Create Date] ) = YEAR ( TODAY () )
            && MONTH ( Table1[Create Date] ) = MONTH ( TODAY () ),
        "Yes",
        "No"
    )

Regards