SEOUL, Aug. 27 (Yonhap) — South Korea’s national burden ratio rose for the sixth consecutive year in 2019 to surpass 27 percent, a parliamentary report showed Thursday.

The ratio, or the percentage of tax revenue and social security contributions to gross domestic product (GDP), came to 27.3 percent last year, up 0.6 percentage point from the prior year, according to the report from the National Assembly Budget Office.

It marks the first time that the ratio has exceeded the 27 percent level.

Yet, it was 7.3 percentage points lower than the average rate in 2018 for members of the Organization for Economic Cooperation and Development.

Last year’s was attributed to greater social security contributions stemming from South Korea’s expansion of various welfare programs.

South Korea’s tax burden ratio, or the portion of tax revenue to GDP, stood at 20 percent in 2019, up 0.1 percentage point from a year earlier.

The marginal increase came as the country’s tax revenue grew by only 6 trillion won (US$5.1 billion) last year from the previous year.

As of 2018, the average tax burden ratio among OECD members amounted to 24.9 percent, according to the report.