Fortnightly's Field Guide to CEOs

They just don't make 'em like they used to. CEOs, that is. Where once CEOs could count on at least a decade of chauffeur-driven limos, stock options, and seven-figure bonuses, in today's hostile habitat, CEOs have a shrinking lifespan. That is the conclusion of a Booz Allen Hamilton (BAH) study on CEO turnover.

In just the last six years, the worldwide mean tenure of all CEOs has dropped two years, from 9.5 in 1995 to 7.3 in 2001. And they're getting younger, too: the average age of North American CEOs was 50.4 in 1995; last year it was 48.8.

BAH divided CEO succession events into three categories: merger-driven, performance-related, and regular transition. For those CEOs that departed due to performance reasons, it was mostly due to the law of the jungle: Even if their performance was strong in the first half of their tenure, when they stopped coming back from the hunt with higher stock prices, they were pushed aside.

One slightly positive note: BAH's "CEO Safety Index" puts the energy industry* near the top of the CEO stability charts. But don't take too much comfort, because the data in the study is from CEOs departing in 2001-before the tidal wave of change the industry saw in 2002.

Don't expect the trend toward higher CEO churn rates to reverse. If anything, the BAH study predicts that boards will be terminating CEOs in under-performing companies more and more quickly.

But enough of dry statistics. Use our handy guide to divine your CEO's future.