South Korean manufacturers' business sentiment weakened sharply in the third quarter due to global economic slowdown and fragile domestic demand, a government report showed Wednesday. According to a survey by the Ministry of Knowledge Economy, the business survey index (BSI), which measures manufacturers' assessment of current economic conditions, dropped to 84 during the July-September period from 95 for the previous three-month period. The findings were based on polls of 508 manufacturing companies conducted between Sept. 3 and 21. A reading below 100 means the number of manufacturers with negative opinions exceeded those with positive views. The ministry attributed the third-quarter drop to concerns over the delayed global economic recovery and the weakening consumer sentiment. The International Monetary Fund (IMF) lowered its 2012 global economic growth outlook to 3.3 percent on Monday from 3.5 percent estimated in July. The consumer sentiment index (CSI) continued to fall to 99 in September after rising to 105 in May. The BSI for exports tumbled to 86 in the third quarter from 96 three months before, with the figure for domestic demand declining from 93 to 85 over the cited period. The BSI for the fourth quarter, which gauges manufacturers' outlook on business conditions for the upcoming quarter, came in at 95, down from 101 in the prior quarter and falling below the benchmark level of 100. The results indicated that manufacturers worried about the further worsening of economic conditions in the fourth quarter, the ministry said, promising that it will make its best to boost exports and domestic demand.