DAX Average for year

Hi,
I do have what I want but is there a better way of doing this?
I want to calculate the average sales for each year based on the sum of monthly totals,

I've first tried;

 Avg M per Y:=CALCULATE([Trev],ALL('Calendar'),VALUES('Calendar'[Year])) /12

Which give the total per year and then divides by 12, after a few more attempts I used crossjoin with ALL and VALUES;

  AvgTest:=AVERAGEX(CROSSJOIN(VALUES('Calendar'[Year]),ALL('Calendar'[Month])),[Trev])

so if anyone knows a better way please let me know.


Richard.