Since 2011, Equilar has worked together with the Associated Press on annual CEO pay studies. The 2017 version identifies trends in compensation awards for CEOs who served in that role at an S&P 500 company for at least two years as of fiscal year end 2016. Companies must have filed a proxy between January 1st and May 1st of this year to be included in this study. This sample size creates a consistent comparison for year-over-year changes to pay awards for these CEOs. To see the results, please click here .