Vietnam's Customs office reported in July 2013 that the total value of international merchandise trade for the first half of 2013 was US$124 billion, which was 15.7% higher than the same period in 2012. Mobile phones and their parts were both imported and exported in large numbers, while in the natural resources market, crude oil was a top-ranking export and high levels of iron and steel were imported during this period. The U.S. was the country that purchased the highest amount of Vietnam's exports, while Chinese goods were the most popular Vietnamese impor