stop slicer from affecting measure

[nick9one1]

I have the following visual with two sets of values 

Sum of performanceScore - this shows the monthly score of the selected site in the slicer. 
AllSitePerformanceScore. This is a measure that should show the average of all sites

I cant find a way to stop the DAX being filtered from the slicer..
I tried this but I think it only works to remove filters, not a slicer.  

allSitePerformance = CALCULATE(
AVERAGE('PMMS Submission_Total_Scores'[performancescore]),
REMOVEFILTERS('PMMS Site_Items'[cr20b_site])
)

[nick9one1]

Thanks for the reply. 

Both of those solutions give an error - 

There are no typos, but I f I change the first reference of 'PMMS Site_Items'[cr20b_site] to 'PMMS Submission_Total_Scores'[performancescore], the error goes away. 

Unfortunately they dont work and the slicer is still filtering the metric 

[amitchandak]

@nick9one1 , Try measure like

allSitePerformance = CALCULATE(
AVERAGEX(Values('PMMS Site_Items'[cr20b_site]) , 'PMMS Submission_Total_Scores'[performancescore]),
REMOVEFILTERS('PMMS Site_Items'[cr20b_site])
)

or remove all filters 
allSitePerformance = CALCULATE(
AVERAGEX(Values('PMMS Site_Items'[cr20b_site]) , 'PMMS Submission_Total_Scores'[performancescore]),
REMOVEFILTERS('PMMS Site_Items')
)