How to find related next record after last occurrence of a negative value in a table

[penumatsas]

I have table as shown below and i need to find date for a given Region which has backlog as positive number after the last record which has negative backlog for that  particular region.

Region	Date	Backlog
A	5/1/2019	10
A	5/2/2019	-1
A	5/3/2019	100
A	5/6/2019	-2
A	5/8/2019	200
A	5/9/2019	100
B	5/1/2019	20
B	5/2/2019	-10
B	5/3/2019	30
B	5/6/2019	40
B	5/8/2019	30
B	5/9/2019	40

Result Needed:

Region	Target Date
A	5/8/2019
B	5/3/2019

How to accomplish it?

[Zubair_Muhammad · Accepted solution]

@penumatsas 

This mEASURE works with your sample data

Measure =
VAR LastNegative =
    MINX ( TOPN ( 1, FILTER ( Table1, [Backlog] < 0 ), [Date], DESC ), [Date] )
RETURN
    MINX (
        TOPN (
            1,
            FILTER ( Table1, [Backlog] >= 0 && [Date] > LastNegative ),
            [Date], ASC
        ),
        [Date]
    )