First and Last Date a product was bought

Could put this in one column, but is easier to see in three: 

Earlier has the rank from earliest (1) to latest (N), Latest is reversed. 

Earlier = CALCULATE(COUNTROWS(Purchases),
    FILTER(ALL(Purchases), Purchases[Product] = EARLIER(Purchases[Product])&&Purchases[Purchase date] <= EARLIER(Purchases[Purchase date]))

Later = CALCULATE(COUNTROWS(Purchases),
    FILTER(ALL(Purchases), Purchases[Product] = EARLIER(Purchases[Product])&&Purchases[Purchase date] >= EARLIER(Purchases[Purchase date]))

Status = IF([Earlier]=1, "Earliest",IF([Later]=1,"Latest",BLANK()))

Boycie92

Hi, Please try with this Calculated Column:

Identifier =
VAR FirstTransactionDate =
    CALCULATE (
        FIRSTDATE ( Table1[Transaction Date] ),
        FILTER ( Table1, Table1[Product ID] = EARLIER ( Table1[Product ID] ) )
    )
VAR LastTransactionDate =
    CALCULATE (
        LASTDATE ( Table1[Transaction Date] ),
        FILTER ( Table1, Table1[Product ID] = EARLIER ( Table1[Product ID] ) )
    )
RETURN
    SWITCH (
        TRUE (),
        Table1[Transaction Date] = FirstTransactionDate, "First",
        Table1[Transaction Date] = LastTransactionDate, "Last",
        BLANK ()
    )

Regards

Victor

Lima - Peru