The nation posted a trade surplus for the 18th straight month in July as its exports marked a monthly record.

The Korea Customs Service said on Tuesday that the nation’s exports totaled 50-point-six billion U.S. dollars in July, while imports reached 44-point-three billion dollars. The nation’s trade surplus thus came in at six-point-three billion U.S. dollars for July.

Exports marked a monthly record last month, growing five-point-eight percent from a month ago, which is larger than the 48-point-six billion dollars posted in April.

The service attributed the strong result to the nation’s mainstay export items, such as petroleum products, shipbuilding and vehicles.