South Korea's trade surplus reached a three-year high of more than $6 billion in May, UPI quoted the government as saying Saturday. The surplus for the month -- the 16th consecutive month trade has been in the black -- is more than double the $2.39 billion surplus in May 2012, news agency Yonhap reported. Exports rose 3.2 percent from the same month of 2012 to $48.37 billion. Imports over the same period fell 4.8 percent to $42.34 billion, the government said. Growing demand from the United States was a big reason beyond the surging surplus. After a sharp downturn, exports of mobile telecommunication devices rose 62.5 percent from May 2012. Exports of automobiles to the United States rose 17.4 percent over the same period and petrochemical exports rose 6.2 percent year-over-year, the Ministry of Trade said.