Remarks

The <Dates> argument can be any of the following:

• A reference to a date/time column. Only in this case a context transition applies because the column reference is replaced by
  • CALCULATETABLE ( DISTINCT ( <Dates> ) )
• A table expression that returns a single column of date/time values.
• A Boolean expression that defines a single-column table of date/time values (when used in a CALCULATE filter argument).

ENDOFMONTH filters <Dates> into a 1-row, 1-column table that shows only the latest date, in the entire <Dates> column devoid of all filters, that is in the same year and month as the latest visible date in <Dates>.

The following ENDOFMONTH call

ENDOFMONTH ( 'Date'[date] )

is a more efficient implementation of the following semantically equivalent expression:

VAR LastDateVisible =
    CALCULATE ( MAX ( 'Date'[Date] ) )
VAR LastYearVisible =
    YEAR ( LastDateVisible )
VAR LastMonthVisible =
    MONTH ( LastDateVisible )
VAR DaysInMonth =
    FILTER (
        ALL ( 'Date'[Date] ),
        YEAR ( 'Date'[Date] ) = LastYearVisible
            && MONTH ( 'Date'[Date] ) = LastMonthVisible
    )
VAR LastDayInMonth =
    MAXX (
        DaysInMonth,
        'Date'[Date]
    )
VAR Result =
    CALCULATETABLE (
        VALUES ( 'Date'[Date] ),
        'Date'[Date] = LastDayInMonth
    )
RETURN
    Result