Grouping data

Hello, 

I need to sum grouping data. For example: 

- I have two months 

- 1st we have 9 000 sales and 10 000 target

- 2nd we have 3 000 sales and 6 000 target

wehn I count progression for months it is:

- 1st -  9 000/10 000 = 90%

- 2nd - 3 000/5 000 = 60%

When I look at year I have (9 000+3 000)/(10 000+ 5 000)= 80%, but for the contest i need to left monthly values (90% and 60%) but when I look on year i need to sum this score (0,9+0,6=1,5)

I know that i can use calculate for every single month and then just recived resoults - but it is too many measures to do it. I think about way to do it easier. 

Anyone can halp me? I am very begginer in Power BI.