SEOUL-- Listed units of South Korea's top 10 conglomerates saw their operating incomes almost double to a record high in the first three quarters of the year, with chip giants Samsung Electronics Co. and SK hynix Inc. taking up more than half of the total, a market tracker said Monday.

The combined operating profit of the companies came to 62.5 trillion won (US$57.5 billion) in the January-September period, up 95.4 percent from a year earlier and the highest for the first three quarters, according to Chaebul.com.

The amount was also higher than their full-year operating profit of 44.5 trillion won in 2016, with their operating income estimated to reach 80 trillion won for all of 2017.

Their sales stood at 592.5 trillion won in the nine-month period, up 12.8 percent from the same period a year earlier.

Samsung Electronics saw its operating profit skyrocket 178 percent to 23.6 trillion won over the cited period, with that of SK hynix rising nearly five times to slightly over 9 trillion won.

The combined operating income of the two chip behemoths accounted for 52.2 percent of the total operating profits of the companies during the period, up 31.3 percent from a year earlier.

Listed units of top conglomerate Samsung Group posted the largest operating income of 27.5 trillion won among the leading business groups, up 171 percent from a year earlier.

SK Group followed with 13.5 trillion won, up 213 percent, and LG Group ranked third as the operating income of its listed units jumping 98 percent to 6.2 trillion won.

In contrast, Hyundai Motor Group, whose flagships are South Korea's top two automakers Hyundai Motor Co. and Kia Motors Corp., suffered a 22.7 percent drop to 5.5 trillion won.

Despite their strong earnings, the combined workforce of the listed companies stood at slightly over 625,000 as of the end of September, up a mere 1.5 percent from a year earlier.

Source: Yonhap News Agency