The reading marks 22 consecutive months of on-year decline in the index.

The trade terms index measures the amount of imports a country can purchase for each unit of exports. 

A reading below 100 means import prices are higher than those of exports, resulting in unfavorable terms of trade.

The country's exports have dropped for 10 consecutive months since December and are expected to fall again this month with outbound shipments plunging 19.5 percent on-year in the first 20 days.

In September, the country's export volume index slipped 2.1 percent from the same month last year, while its import volume index gained 1.6 percent over the cited period.

South Korea still continues to post a sizable trade surplus each month, with its trade surplus coming to $5.97 billion last month, marking 92 consecutive months of trade surplus.

The steady decline in exports is largely attributed to the trade dispute between the US and China that are the world's largest importers of South Korean goods, along with a prolonged downturn in the global semiconductor market.

Earlier this week, the BOK said the local economy may grow at the slowest pace in a decade this year partly due to such global uncertainties that continue to cause problems for the export-dependent country. (Yonhap)