Not all CEOs are created equally.
Executive recruitment firm Kittleman ranked the top 50 CEOs based on their impact on the average monthly revenue generated during their tenure as the top executive at their respective companies.
The cash generated under Cook is far and away the most of any other CEO on the list.
Nearly half of the companies that were scrutinized, 24 of 50, saw revenue impacted when the CEO was approximately four to eight years into the position.
Only 10% of the companies on the list had female CEOs at the helm, four of which -- Hewlett Packard (HP) , Lockheed Martin (LMT) , General Motors (GM) , and General Dynamics (GD) -- grew significant revenue in five years or less.
Mary T. Barra of GM received a special shout out in the report for turning around GM with average growth of $218 million per month after just 48 months considering the company filed for bankruptcy in 2009.
Here is the full CEO list with rankings.