CEO Trends.

• Position: Director Data - Chief executive officers

Record number of CEOs reached retirement age

* In 2017, nearly 17% of sitting CEOs reached retirement age (64 or older). That's the highest rate since we began tracking successions.

Outsider CEOs gained steam

* Outsiders filled around 44% of vacancies. In both 2015 and 2016, they filled about 14%.

The best CEOs left less often

* The CEO succession rate at better-performing companies declined to about 7%, the lowest since 2002. This likely reflects...