Chief executive officer turnover had the biggest year-over-year drop of the past decade in 2010, reaching its lowest rate since 2003, Booz & Co. said. A total of 291 CEOs left their companies last year, the New York-based management consulting firm said in a report this week.

CEO succession at the world’s 2,500 largest public companies by market capitalization last year declined 19 per cent to 11.6 per cent, the lowest rate since 2003. China’s 5.2 per cent turnover rate contributed to the overall decline, and Japan had the highest rate, according to a statement announcing the study.

CEOs are increasingly based in emerging markets as more than one-fourth of the biggest 2,500 companies have their headquarters in an emerging economy.

The number of companies based in the U.S., Canada and western Europe fell about 28 percent from 2000, the study showed.

Asia had 895 of the top companies versus 772 in North America and 619 in Europe.

“Could this suggest that global enterprise is nearing a geographic tipping point?,” Booz & Co. said. “Within a few years, if this pattern continues, the companies in the world’s mature Western economies could represent a minority of our sample.”

CEOs forced from office dropped to 2.2 percent last year, while planned departures fell to 7.7 percent. In 2009, the succession rate was 11 percent in North America, 10 percent in Europe, 19 percent in Japan and 10 percent in the rest of Asia.

More CEOs were chosen from within the company, according to the study. Insiders left after an average 7.1 years versus 4.3 years for outsiders, and last year they produced a 4.6 percent shareholder return on a regionally adjusted basis compared with 0.1 percent for outsiders.

The mean CEO tenure was 6.6 years in 2010, 18 months shorter than in 2000.

Fewer CEOs are also chairmen, and only 14 percent of incoming CEOs in North America had both titles, versus 52 percent in 2001.

The average appointment age was 52.2 in 2010, compared with 50.2 in 2000.