Nexen Tire Corp., South Korea\'s third-largest tiremaker, said Friday that its third-quarter operating profit fell 8.5 percent from a year earlier due mainly to unfavorable foreign exchange rates. Operating profit came to 33.5 billion won (US$30.3 million) in the July-September period, compared with 36.6 billion won in earnings tallied a year earlier, the company said in a regulatory filing. Shares of Nexen Tire closed at 18,750 won on the Seoul bourse, down 4.09 percent from the previous session. \"The drop is manly attributed to exchange rates that cut into export earnings,\" Nexen said. It said despite the annual drop in operating profits, the company\'s earnings soared 23.0 percent compared to the second quarter of this year when numbers hit 27.2 billion won. The company did not release net profit figures for the quarter. The tiremaker added that sales surged 22.6 percent on-year to a quarterly high of 366.4 billion won, fueled by increased domestic and overseas demand. It said improved quality, better brand image and productivity contributed to strong sales. Nexen Tire, meanwhile, said that sales will likely improve in the coming months as it moves to increase overseas production.