RETENTION

Hi Andrew_na_lang ,

Please have a try.

Retention =
VAR SelectedDateRange = SELECTEDVALUE('Date'[Date])
VAR Today = TODAY()
VAR DaysBetween = DATEDIFF(EARLIER('Orders'[time_pickup_date]), Today, DAY)
VAR RetainedCustomers =
    CALCULATE(
        DISTINCTCOUNT('Orders'[customer_id]),
        FILTER(
            'Orders',
            DaysBetween >= 31
                && DaysBetween <= 60
                && 'Orders'[time_pickup_date] >= SelectedDateRange - 30
                && 'Orders'[time_pickup_date] <= SelectedDateRange - 1
        )
    )
VAR ChurnedCustomers =
    CALCULATE(
        DISTINCTCOUNT('Orders'[customer_id]),
        FILTER(
            'Orders',
            DaysBetween >= 31
                && DaysBetween <= 60
                && ('Orders'[time_pickup_date] < SelectedDateRange - 30 || 'Orders'[time_pickup_date] > SelectedDateRange - 1)
        )
    )
RETURN
    SWITCH(
        TRUE(),
        RetainedCustomers = 0 && ChurnedCustomers = 0, BLANK(),
        RetainedCustomers = 0, "Churned",
        ChurnedCustomers = 0, "Retained",
        RetainedCustomers, "Retained",
        "Churned"
    )

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