When it is said: 'ABC' Stock is trading at 22 times forward year earnings, then who decides this '22 times'?

FY 17 would mean financial year 16/17 starting Apr 2016 ending March 31st 2017. Research analysts try to figure out the earning per share for the future using various methods.

You divide the current stock price by the earning per share, you get the forward year earnings. But as you must have guessed by now, this is not sacrosanct. Analysts could be wrong in their prediction of a company’s future earnings, and analysts might differ in their views about it as well.


I also want to know when FY17 Earnings are considered then whether they are for the whole 4 quarters of the year or what?