Tax collected on wage income came to more than 30 trillion won for the first time in the country's history last year, the government said Saturday, apparently indicating a growing tax burden on waged workers.

   In 2016, wage income tax came to 31 trillion won (US$26.96 billion), up 14.6 percent from a year earlier, according to the finance ministry.

   The rate of increase outpaced an 11.3-percent on-year rise in overall tax revenue, which came to 242.6 trillion win last year.

   The 2016 tally on wage income tax also marks a significant rise from the government's earlier estimate of 29.2 trillion won, according to government officials.

   Such an increase follows years of criticism from waged workers who insist that only their incomes are transparent when many, especially those who are self-employed, continue to hide their taxable income.

    An earlier report from a local think tank, the Korea Economic Research Institute, has noted only 71.5 percent of all people were currently imposed composite income tax, tax imposed on all income instead of just wage income.

   The National Tax Service too has reported that only 72.8 percent of total earnings of self-employed people were subject to income tax in 2014, meaning the remaining 27.2 percent had either been hidden or gone unnoticed.

   Wage income tax, on the other hand, has been on a steady rise, growing to 25.4 trillion won in 2014 from 19.6 trillion won in 2012, then again to 27.1 trillion won in 2015, according to the finance ministry.

   Composite income tax amounted to 14.3 trillion won in 2016, up 12.2 percent from the year before.

   Inheritance and donation tax came to 5.4 trillion won, up 6.1 percent over the cited period.

   In 2016, wage income tax accounted for 12.8 percent of overall national tax revenue, compared to 8.8 percent in 2006, it said. (Yonhap)