Power BI - Prior Month Values and % Change for a existing measure which aggregates from daily to monthly

I have a table with daily observations. I have an existing measure (Total_Visits_Sum) that provides the data on a monthly or quarterly basis based on the date I use for the axis. If I use a custom column in the calendar for MMM-YY the data automatically gets aggregated.

SUMMARIZE (
    'Data',
    'Data'[Date]),
    CALCULATE (
    SUM ( 'Data'[Visits])))

My question is how do I get the prior month's value to compare, so I could do a month-over-month change? I have seen the examples that do this but only when the underlying frequency of the data is monthly, not aggregated like I am doing.

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