South Korea's terms of trade continued to improve from a year earlier in November, but largely because import prices dropped at a faster clip than export prices, central bank data showed Thursday.

The terms of trade index came to 100.83 last month, up 9.1 percent from the same month last year, according to preliminary data from the Bank of Korea.

The index gauges the amount of imports a country can purchase for each unit of exports, which shows how the country's exports are doing in comparison with those of other countries. A reading above 100 means the country can purchase more for each unit it ships abroad.

The November tally marks the 15th consecutive month of on-year gain, but it also marks a 0.7 percent drop from a revised 101.51 in October.

The on-year rise was attributed to a large cut in import prices.

"The terms of trade index in November grew 9.1 percent from the same period last year as import prices dropped at a faster clip than export prices," the BOK said in a press release.

In November, export prices dipped 13 percent from the same month last year while import prices plunged 20.3 percent over the cited period, it added.

A large drop in overall imports apparently helped further improve the country's terms of trade.

The country's imports tumbled 17.6 percent on-year to $34.07 billion last month, while its exports only slipped 4.7 percent to $44.43 billion, the trade ministry said earlier. South Korea's exports have fallen every single month since the start of the year, but cuts in imports have also outpaced those in exports each month.

With the large cut in imports in November, the country's income terms of trade index also continued to improve significantly.

The index, which measures the amount of imports that can be purchased or exchanged with the total value of exports, surged 9.9 percent on-year to 135.89 last month. (Yonhap)