Different Average - filtered items and total for a group not zero

[FPP]

I have the following table

Date	Key	Status	Amount
Jan 1,2020	A1	open	5
Jan 1,2020	A1	closed	10
Jan 1,2020	A1	closed	20
Jan 1,2020	A2	closed	5
Jan 1,2020	A2	closed	0
Jan 1,2020	A3	closed	0
Jan 1,2020	A4	open	40
Jan 1,2020	A5	closed	50
Jan 1,2020	A5	closed	-50
Jan 1,2020	A5	open	30

I want the following:

numerator= SUM (Amount) where Status = 'closed' AND Amount <> 0 (Not a big deal to add the zero, since it doesn't change the SUM)
denominator= COUNT of DISTINCT(Key) where Status = 'closed' AND SUM(Amount grouped by the key) <> 0 
Ans: numerator/denominator

So for above:
numerator=10+20+5+0+50-50=35
denominator=2

Ans = 35/2 = 17.5

OR

numerator=10+20+5=35
denominator=2

Ans = 35/2 = 17.5

OR

numerator=30+5=35
denominator=2

Ans = 35/2 = 17.5

How can I do this in DAX?

[AlexisOlson · Accepted solution]

I think this should do the trick:

DifferentAverage =
CALCULATE (
    DIVIDE (
        SUM ( Table1[Amount] ),
        COUNTROWS (
            FILTER (
                SUMMARIZE ( Table1, Table1[Key], "KeySum", SUM ( Table1[Amount] ) ),
                [KeySum] <> 0
            )
        )
    ),
    Table1[Status] = "closed"
)

[FPP]

It worked.  Thank you!