The average term of a chief executive officer at listed firms was 31 months, data showed on Sunday.

It was also found that a single firm reseated its CEO an average of 3.7 times over the past 10 years, according to data released by Chaebul.com, a website that provides information on the country’s conglomerates. The survey was conducted on 992 listed firms.

A firm that changed its chief executive in a two-year term was discovered to record better earnings, it said.

Accumulated sales and net income of the 162 companies, which reshuffled their top position every two years, grew 126.7 percent and 103.9 percent in 2010, respectively, when compared with the figures from 2000, said the data.

As an exemplary case, the overall sales of Samsung Electronics rose to 112.24 trillion won ($103.8 billion) last year, up 227.4 percent from 34.29 trillion won in 2000 and its net profit reached 13.23 trillion won, up from 6.01 trillion won in the same period.

Hyundai Motor Co.’s accumulated sales also topped 36 trillion won last year, a sharp increase from 18.23 trillion won in 2000, and its net income soared 668.6 percent to 5.26 trillion won from 667 billion won in the past 10 years.

The overall sales of 131 conglomerate-owned firms, which did not change its CEO for the 10-year term, saw an increase of 110.2 percent, however, their net income rose to a lower-than-average 51.1 percent, it said.

Meanwhile, the firms that reseated chiefs more often than every two years showed poorer performance, the data noted.

Listed firms that repositioned their top heads seven times during the 10 years recorded an increase of 55.6 percent in sales and 16 percent in net profit in 2010. Those that changed CEOs every year also showed sales increases of 37.2 percent during 2000 to 2010.

By Cho Ji-hyun (sharon@heraldcorp.com)