Calculate total previous year points earned based on decimal customer length and customer type?

Hi, alya1

Thanks for ryan_mayu's concern about this issue.

I am glad to help you.

According to your description, you can refer to my DAX formula New Column:

TotalPointsLastYear =
VAR CustomerLength = [Length (yrs)]
VAR CustomerType = [Customer Type]
VAR PointsPerDay =
    SWITCH (
        TRUE (),
        CustomerType = "A"
            && CustomerLength < 3, 5,
        CustomerType = "A"
            && CustomerLength >= 3, 10,
        CustomerType = "B"
            && CustomerLength < 3, 10,
        CustomerType = "B"
            && CustomerLength >= 3, 20,
        CustomerType = "C"
            && CustomerLength < 1, 10,
        CustomerType = "C"
            && CustomerLength >= 1
            && CustomerLength < 5, 20,
        CustomerType = "C"
            && CustomerLength >= 5
            && CustomerLength < 10, 30,
        CustomerType = "C"
            && CustomerLength >= 10, 40
    )
VAR PreviousTierPoints =
    SWITCH (
        TRUE (),
        CustomerType = "A"
            && CustomerLength < 3, 5,
        CustomerType = "A"
            && CustomerLength >= 3, 5,
        CustomerType = "B"
            && CustomerLength < 3, 10,
        CustomerType = "B"
            && CustomerLength >= 3, 10,
        CustomerType = "C"
            && CustomerLength < 1, 10,
        CustomerType = "C"
            && CustomerLength >= 1
            && CustomerLength < 5, 20,
        CustomerType = "C"
            && CustomerLength >= 5
            && CustomerLength < 10, 20,
        CustomerType = "C"
            && CustomerLength >= 10, 30
    )
VAR FractionNewTier =
    CustomerLength - FLOOR ( CustomerLength, 1 )
VAR FractionOldTier = 1 - FractionNewTier
RETURN
    ( FractionNewTier * 365 * PointsPerDay ) + ( FractionOldTier * 365 * PreviousTierPoints )

Here are my test results:

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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