The pace at which part-time workers’ incomes have grown slowed last year to one-third of the previous year's.

A survey conducted on 17-thousand part-time workers by Alba.co.kr, a job posting site specializing in part-time jobs, showed that such employees in South Korea earned an average monthly income of 653-thousand-391 won, or roughly 547 U.S. dollars, last year.

The amount was only two-point-seven percent higher than that in 2014, when the figure grew eight-point-two percent from the previous year's.

In particular, part-timers’ income grew only zero-point-eight percent in the fourth quarter of last year, marking the first time the quarterly income growth rate fell below one percent since the survey was first conducted in 2013.

The Web site attributed the slower income growth to shrinking demand for part-timers as a result of the economic slump induced by sluggish consumption and a growing number of small businesses declaring bankruptcy.