looking at the colors of the months fully within the time period, we can approximate that:
April's average is 0.975
May's average is 1
Jun's average is 1.01
July's average is 1.03
August's average is 1.005
September's average is 1.06
Assuming that the end of March and the majority of October roughly cancel each other out, we can assign all other points to be 1.
Now, we must average the numbers together.