SEOUL -- Sentiment of South Korean businesses over the economic situation continued to worsen this month due to lackluster non-manufacturing activities, central bank data showed Friday.

The composite business sentiment index (CBSI) in all industries slipped 0.6 points over the month to 85.3 in February, keeping a downward trend for the fourth straight month, according to the Bank of Korea (BOK).

The index tumbled from 91.8 in November last year to 87.3 in December when the impeached President Yoon Suk-yeol declared an emergency martial law which was revoked by the National Assembly hours later.

The index kept hovering below the long-term average of 100 amid the lingering economic uncertainties.

The CBSI among manufacturers added 1.1 points to 90.1 in February compared to the previous month on the back of improved exports in some industries, such as the chip-making sector.

The index for non-manufacturers declined 1.9 points to 81.7 owing to the sluggish housing market and the faltering private consumption.

The results were based on a survey of 1,867 manufacturers and 1,445 non-manufacturers conducted between Feb 6 and 13.

Manufacturers picked sagging domestic demand, economic uncertainties and expensive raw materials as key barriers to doing business, while non-manufacturers selected domestic demand slump, uncertain economic situations and higher labor costs.

The economic sentiment index (ESI), which reflects sentiment among both businesses and consumers, stood at 90.2 in February, up 3.5 points from the previous month.