The average length of service for employees of Korea's leading companies has been steadily rising in recent years despite a prolonged economic slump and wave of restructuring, data showed Wednesday.

According to the data by market researcher CEO Score, the average years of service for workers of 322 major companies grew to 11.6 years in 2015 from 11.3 years a year earlier. The figure stood at 11.1 years in 2013.

The duration of service for workers of the nation's top 30 family-controlled conglomerates also became longer over the cited period, despite a drop in their payrolls. Their length of service averaged 11 years in 2015, up from 10.7 years in 2014 and 10.5 years in 2013.

The increase came as affiliates of the leading conglomerates cut a combined 4,500 jobs last year, or 0.4 percent of their total workforce.

Market watchers attributed the steady increase in the workers' length of service to a fall in employment by major companies and the slow pace of overall corporate restructuring.

According to the data, Daewoo Shipbuilding & Marine Engineering, one of the main targets of a government-led restructuring drive, posted the longest length of service with 16.8 years in 2015, followed by tobacco maker KT&G with 16.5 years, major shipbuilder Hyundai Heavy Industries and top automaker Hyundai Motor with 15.6 years. State-run companies had the longest length of service at 16.1 years in 2015, trailed by makers of cars and auto parts with 16 years, telecom companies with 15.8 years and banks with 15 years.

The average length of service for male workers stood at 12.7 years in 2015, with the comparable figure for women reaching eight years, according to the data.

The data comes as Korea is mired in sluggish economic growth. Stung by slumping exports and stubbornly weak domestic demand, Asia's fourth-largest economy grew 2.6 percent on-year in 2015, down from a 3.3-percent expansion a year earlier.

The government is also pushing to restructure financially troubled shipbuilders, shipping lines and others that have been struggling under the weight of snowballing losses and debts, in a preemptive bid to keep their sudden collapses from weighing on the overall economy. (Yonhap)