The number of newly established firms in South Korea soared to the highest level in five years last year as more people opted to start their own business after retirement, data showed Wednesday.

A total of 84,697 companies were newly established in 2014, compared with 75,578 firms in the previous year, according to the Bank of Korea and the Small and Medium Business Administration.

The on-year gain of 9,119 companies marks the sharpest increase since the on-year rise of 15,102 in 2009.

The gain has been led by people who are aged over 50. The portion of new business owners that were 50 years or older accounted for 32.6 percent of the total in 2013, up from 26.7 percent in 2008. The data for 2014 was not available.

Meanwhile, the number of firms that went bankrupt last year came in at 841 firms, down from 1,001 companies in 2013.

The default rate of corporate bills ― bonds, checks and promissory notes ― came in at 0.19 percent last year, up from 0.14 percent in 2013.

The central bank blamed the increase on a rise in default corporate bills of the cash-strapped conglomerates Tong Yang and STX. (Yonhap)