According to data by the National Tax Service obtained by main opposition Democratic Party Rep. Yang Kyung-sook, unpaid school loans stood at 55-point-two billion won last year, up two-point-seven fold from just over 20 billion in 2018.

The number of delinquents also rose two-point-six fold in the cited period from over 17-thousand to some 44-thousand-200 last year.

Under a post-employment repayment scheme, university students can take out loans to pay for their full tuition and living expenses and pay back after they land a job.

This system was introduced in 2009 after existing school loan programs came under fire for pushing students to pay back their debt regardless of employment status, turning them into credit delinquents.

Under the scheme, the National Tax Service begins to retrieve loans when the borrower's annual income in the previous year exceeds a certain level.

Last year, over 291-thousand-800 people met this condition, in a near 58 percent jump from 2018.