South Korea's terms of trade deteriorated for the 16th consecutive month in March. 

The Bank of Korea said on Wednesday that the net terms of trade index for products stood at 92-point-27 last month, down five-point-one percent from a year earlier.

The index measures the amount of imports a country can purchase for each unit of its exports. It's calculated by dividing the price of exports by the price of imports and then multiplying the result by 100, with a reading over 100 meaning more capital enters the country through trade. 

Both exports and import prices fell on-year last month, but the decline seen in export prices was steeper at six percent as opposed to import prices’ contraction of one percent.