There are three characteristics of the data that complicate this procedure. First, CEOs often hold options that they received before they became CEO. Second, the exercise price is sometimes missing. Third, the proxies report option gains as a dollar value, so it is impossible to determine exactly which options were sold in a given year. We are helped, however, by the fact that proxies sometimes contain information on the total number of options held by the CEO (or alternatively the total number of vested options held by the CEO). This information on total options allows us to test the accuracy of.
