Comparing Dates from 2 tables

Hi PowerBI123456 ，

If your notes date table has single notes date for each account number, you can create a measure like this to count:

Count =
VAR tab =
    FILTER (
        ALL ( Payment ),
        'Payment'[Payment date]
            > CALCULATE (
                MIN ( 'Notes'[Note date] ),
                'Notes'[Account number] IN DISTINCT ( 'Payment'[Account number] )
            )
    )
VAR tb =
    SUMMARIZE (
        ADDCOLUMNS (
            tab,
            "Count",
                COUNTX (
                    FILTER ( tab, [Account number] = EARLIER ( Payment[Account number] ) ),
                    [Payment date]
                )
        ),
        [Account number],
        [Count]
    )
RETURN
    COUNTX ( FILTER ( tb, [Count] > 1 ), [Account number] )

Attached a sample file in the below, hopes to help you.

Best Regards,
Community Support Team _ Yingjie Li
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