We value stock options based on the Black-Scholes (1973) formula for valuing European call options, as modified by Merton (1973). 5 To construct a measure of the total stock option holdings of each CEO at a given point in time, we use proxy data on stock option grants, gains from exercising stock options, and the total number of stock options held by the CEO. Annual proxies contain information on options granted during the preceding fiscal year, including the number, duration, and exercise price of the options. In order to construct a CEO’s total holdings of stock options, we go back to the first year in.
