Korea Exchange Bank (KEB), South Korea\'s No. 5 lender, said Wednesday that its second-quarter earnings jumped more than eight times from a year earlier on a one-off profit from the sale of a stake in a local builder and improved interest margins. Net income amounted to 1.13 trillion won (US$1.05 billion) in the April-June period, up 726 percent from the previous year, the bank said in a regulatory filing. In the first half, net profit soared 162 percent on-year to 1.33 trillion won. Revenues inched down 9.8 percent on-year to 3.61 trillion won while operating profits jumped 699 percent to 1.49 trillion won, it added. Shares of KEB closed flat at 8,060 won on the main bourse. The results came after the market closed. The improved bottom line came mainly because KEB logged an after-tax one-time gain worth 876 billion won by selling its stake in Hyundai Engineering & Construction Co. KEB\'s net interest margin (NIM), a gauge of profitability, came in at 2.72 percent in the second quarter, up from 2.63 percent three months earlier. Korean banks\' NIMs have been on the rise mainly because they can charge more interest on their lending amid the central bank\'s tightening cycle. KEB saw its financial soundness get stronger as the ratio of non-performing loans declined compared with the preceding quarter. The ratio of substandard loans stood at 1.36 percent, down from 1.44 percent in the first quarter. KEB\'s total assets stood at 98.3 trillion won as of end-June, down from 106.2 trillion won three months ago. Hana Financial Group agreed with U.S. buyout fund Lone Star Funds last month to extend till November a deal to buy a 51.02 percent stake in KEB at a price of 4.41 trillion won. But KEB\'s decision to pay out a record interim dividend to its biggest shareholder Lone Star has drawn strong public criticism that the fund is trying to exit the Korean market after fattening its pockets. Its record quarterly dividend payout ate into its capital adequacy ratio in the second quarter, but KEB said in spite of that, its capital ratio remained higher than local rivals. KEB\'s capital adequacy ratio, a gauge of financial health, reached 14.41 percent last quarter, down from 14.95 percent from the preceding quarter. But its tier-one ratio, a barometer of core capital, rose by 0.39 percentage point to 11.91 percent, the bank said.