calculate mean and standard deviate except last weeks

[Anonymous]

Hi All,

I'm trying to calculate the mean and standard deviation for 12 weeks and my dataset has 13 weeks of data. This is for the purpose of calculating the z value. Following are the measures I tried;

Mean = VAR maxweek = MAX('Last 13 weeks New'[WeekOfYear]) RETURN CALCULATE(AVERAGE('Last 13 weeks New'[#_Cases]),'Last 13 weeks New'[WeekOfYear]<maxweek)

The result of this is 1 for each row

Standard deviation new = VAR maxweek = MAX('Last 13 weeks New'[WeekOfYear]) RETURN CALCULATE(STDEV.P('Last 13 weeks New'[#_Cases]),'Last 13 weeks New'[WeekOfYear]<maxweek)

The result of this is 0 for each row

WeekOfYear is a whole number

Any help on above is much appreciated,

Thanks in advance,

Best Regards,

Ashan Meegoda.

[Anonymous]

Hello @Anonymous 
Can you please provide some sample data in table format with the expected output after removing sensitive information?
Please check this link