I want to design a chart with moving 12 months' averages .
The line chart is supposed to have 2 components(lines) :
1st line:12 month moving average for total Net Sales of all customers.
2nd line:12 month moving average for total Net Sales of Top 3 customers (out of thousands of customers) only.
I am unable to use moving-average funtion.
Do i need to create a dimension/measure which takes 12 month rolling behaviour into account?
I have used LastPeriods function with some success but can't use it for the second line.
Please refer the image for graph requirement
Please suggest an approach.