June 30 (Bloomberg) -- Zambia’s trade surplus narrowed to 774.8 billion kwacha ($160 million) in May from 1.1 trillion kwacha a month earlier, the Central Statistics Office said.

Exports declined 4.2 percent to 3.4 trillion kwacha and imports rose 7.2 percent to 2.6 trillion kwacha, the Lusaka- based agency said in an e-mailed statement today.

Traditional exports, defined as “mainly metals,” dropped to 2.74 trillion kwacha, it said. The southern African country is Africa’s biggest copper producer.

To contact the editor responsible for this story: Gordon Bell at gbell16@bloomberg.net