Business sentiment in South Korea remains weak for October due mainly to the new coronavirus' impact on major industries, a local think tank said Monday.

The business survey index of the country's top 600 companies by sales came to 84.6 for October, slightly up from the 83.5 for September, the Korea Economic Research Institute (KERI) said in a statement. 

A reading below 100 means pessimists outnumber optimists, while a figure above the benchmark means the opposite.

The BSI has stayed below 100 for 29 consecutive months after reaching 100.3 in May 2018, said KERI, a research institute under the Federation of Korean Industries, the country's biggest business lobby.

KERI's analysis for this month gave an index of 84, up from 79.8 a month earlier as the pandemic prolongs, it said.

KERI said 358 out of the 600 companies responded to the survey, which was conducted from Sept. 15-22. (Yonhap)