How to find the average from the sum of a measure from the last 6 months

[scorbin-j]

I have two measures that sum columns from two different tables. These tables cannot be connected through a relationship, but they are connected to the same date table. 

SUMLaborHours = SUM(Labor[hours])

SUMDefectQty = SUM(Defects[Defect_Quantity])

I then find the Defects Per 1000 Labor Hours with this measure

DefectPerLaborHours = 
    DIVIDE(
        [SUMDefectQty],
        [SUMLaborHours],
        0
    ) * 1000

That gives these numbers for the last 6 months

8.15	2024 05
14.40	2024 06
7.11	2024 07
30.39	2024 08
20.26	2024 09
52.90	2024 10
14.08	2024 11

So I would like to find the average of those numbers. Summing them gives 147.29 which should be an average of 24.54. How can I go about getting that sum and finding that average of the last 6 months? 
Note: This is not calendar months which is why there are more than 6 months listed, but the amount of days equals 6 months. 

[DataInsights]

@scorbin-j,

Here's an example that assumes you've selected the six fiscal months in a slicer or filter.

Average Measure =
AVERAGEX ( VALUES ( 'Date'[YearMonth] ), [DefectPerLaborHours] )

[scorbin-j]

So I probably should have mentioned this, but I want to show that value on a line graph showing the average as a constant line. I have filter on the graph to only go back 6 months, but that measure just seems to follow the original DefectsPerLaborHour measure instead of a constant, single value. 
Something like this: 

[DataInsights · Accepted solution]

@scorbin-j,

Try adding ALLSELECTED to remove date filter context from within the visual but keeping the filter context from the filter on the graph.

Average Measure =
CALCULATE (
    AVERAGEX ( VALUES ( 'Date'[YearMonth] ), [DefectPerLaborHours] ),
    ALLSELECTED ( 'Date'[YearMonth] )
)

[scorbin-j]

That worked! Thanks for your help