Retail investors' stock-related funds have risen by nearly 20 trillion ($18.2 billion) this year on the back of a surging stock market, industry data showed Thursday.

Individuals' stock funds increased by 19.6 trillion won for eight sessions from Jan. 4-13, amounting to nearly 20 percent of last year's total.

Those funds refer to money that retail investors use to buy stocks or deposit at securities companies to purchase shares.

Over the cited period, individuals bought 10.8 trillion won worth of shares, with their deposits at brokerages gaining by 8.8 trillion won.

Last year, retail investors purchased a net 67.7 trillion won worth of stocks on the country's main KOSPI and secondary KOSDAQ markets.

Investor deposits at brokerage houses came to 65.6 trillion won at the end of last year, up from 27.3 trillion won a year earlier.

Market watchers said investors seem to have moved a considerable amount of their money from banks to the stock market, which has been on a roll in recent months.

The benchmark Korea Composite Stock Price Index (KOSPI) surged 22.34 points, or 0.71 percent, to 3,148.29 on the Seoul bourse on Wednesday as investors loaded up on large caps. (Yonhap)