Earnings by South Korea's top four conglomerates accounted for more than 80 percent of the 30 leading business groups' total net profit in 2020 in a show of their dominance in Asia's fourth-largest economy, government data showed Tuesday.

Samsung, Hyundai Motor, SK and LG groups posted a combined net income of 37.6 trillion won ($31.7 billion) last year, up 2.2 trillion won from a year earlier, according to the data that the Fair Trade Commission presented for an annual parliamentary audition.

The figure took up 83 percent of slightly over 45 trillion won registered by the country's 30 leading conglomerates by assets.

The percentage was up 12 points from the previous year, with the total bottom line of the 30 groups declining by about 4.6 trillion won in 2020 from a year earlier.

The top four groups saw their sales drop by 4.6 trillion won to 778.8 trillion won last year, and the combined top line of the 30 conglomerates also decreased by 53.8 trillion won to 1,373.3 trillion won.

But the ratio of the top four's sales to the total increased to 56.7 percent last year from 54.9 percent a year earlier, according to the data.

Market watchers said the figures show the concentration of economic power in the top four conglomerates has deepened over the past five years despite the Moon Jae-in administration's efforts to reform the country's large business groups. (Yonhap)