South Korea's state pension service said Thursday that the size of funds under its management has surpassed the 500 trillion won ($427 billion) mark for the first time ever.

The National Pension Service said its total funds reached 500.2 trillion won as of September, a gain of about 100 trillion won from 2013 and a five-fold increase from 100 trillion won in 2003. Last year, the size came to 469.8 trillion won.

Since 1988, the NPS said it has raised 622.4 trillion won overall, with 122.2 trillion won having been used to pay retirees.

The remaining amount has been invested.

Of all funds collected, 394.4 trillion won came from premiums paid by subscribers, with the rest being generated by investments made in stocks, bonds and real estate. The NPS said that with the size of the fund it manages becoming larger, it is paying greater attention to foreign investments.

The total percentage of money that could be invested abroad is expected to reach 25 percent of total funds in 2019 from 20 percent in 2014.

In 2001, the pension service only put 0.1 percent of its funds or about 100 billion won in foreign investment schemes while this number has surged this year. As of June, the service invested 64.3 trillion won or 13 percent of the total it manages in overseas stocks, with 20.5 trillion won or 4.1 percent of money it controlled, injected into bonds.

Related to the data, the National Assembly Budget Office said that because pensions are critical for retirees and must be given back to subscribers, the NPS needs to take special care not to make risky investments at home or abroad.

"Risk management is of the utmost importance," it said, stressing that in particular, investments in real estate needs to be carefully considered. (Yonhap)