It's Good to Be the CEO

The Journal aside, there's reason to question just how representative the Mercer 350 is. Compensation experts tend to look at far greater numbers of companies when examining pay trends. In a paper on executive pay published last year in the Oxford Review of Economic Policy, Bebchuk looked at the pay practices of the 1,500 largest companies. Paul Hodgson, who writes an annual review of executive pay for watchdog group the Corporate Library, looks at a universe of about 2,000 companies.

Of course, it's not just about sheer numbers. It's also about what companies are left in or out of the pool. For instance, while Home Depot, UnitedHealth and Exxon Mobil (XOM Quote) all have drawn scrutiny in recent months for hefty pay packages recently handed out, don't look for any of those companies -- or their pay data -- on the Mercer list.

But the problem isn't merely that some important companies are left out of the report. It also doesn't consider some major elements of executive pay.

The report focuses on salary, bonuses and long-term incentive awards, typically in the form of stock options or restricted shares of stock. What the report doesn't include are things like executive pension and retirement plans, severance packages, perquisites like taking personal trips on the corporate airplane and income tax payments for accepting those perks. And those things can add up.

At Federal Express , the Mercer data included the $4.6 million in salary and bonus and the 325,000 stock options CEO Fred Smith received last year. But it didn't include the more than $1 million worth of perks he got, such as the $476,000 worth of personal security services.

The compensation pieces that Mercer doesn't include, particularly severance packages and deferred compensation, "potentially are far more valuable than anything the executives received during their career," says Hodgson. Many of the executive perks that have drawn protests in recent years "are not touched on here," he adds.