South Korea’s terms of trade worsened for the 14th straight month in May due to fast-rising import prices of oil and other key commodities, central bank data showed Wednesday.

The nation’s net terms-of-trade index for goods — a gauge of overall trade terms — stood at 85.33 last month, down 10.6 percent from a year earlier, according to the preliminary data from the Bank of Korea (BOK).

The figure, however, was up 1.3 percent from a month earlier, the first on-month rise in four months.

The index is calculated by dividing the index for export prices by that for import prices. It shows the amount of imports a country can buy for each unit of exports.

Import prices of oil and key commodities have been on the rise amid the protracted global supply-chain disruptions and a rebound in demand from the pandemic.

The report showed that import prices jumped 24.3 percent on-year in May, a far faster pace of growth than export prices, which increased 11 percent over the same period.