Senior citizens' medical expenses covered by South Korea's national health insurance jumped on-year in the first half of 2013, data showed Friday, apparently due to the country's fast-aging trend.

According to the data by the National Health Insurance Service (NHIS), medical expenses for people aged 65 and older came to 8.9 trillion won (US$8.2 billion) in the January-June period, up 7.8 percent from a year earlier.

The number accounts for nearly 36 percent of the 24.7 trillion won spent by the firm over the cited period. The combined spending on those aged below 65 came in at 15.8 trillion won, edging up 1.5 percent on-year.

The NHIS spent on average 267,782 won for every elderly citizen, while that of all age groups came to 82,984 won. South Koreans aged below 65 held a comparable figure of 59,753 won.

Senior citizens spent 4.3 days in medical institutions on average every month, which also hovers far above the 1.27 days tallied among younger South Koreans.

Meanwhile, the NHIS collected 20.1 trillion won in insurance premiums over the first half, up 7.6 percent from a year earlier.

On average, each local household paid 90,999 won, up 4.3 percent on-year.

As of end-June, the state health insurance provider covered around 51.3 million policyholders. (Yonhap News)