The nation's trade surplus fell 86.1 percent in May from a year earlier to 80.1 billion yen, the Finance Ministry said Wednesday in a preliminary report.

The fall was the 11th consecutive month of year-on-year decline in the customs-cleared trade surplus. Except for January's 95.3 billion yen trade deficit, the latest figure marked the smallest surplus since the 62.9 billion yen logged in January 1996, a ministry official said.

Due to the U.S. economic slowdown and the subsequent cooling of global demand, Japanese exports in May declined in value and volume, prompting the government to maintain its vigilance regarding export trends, the official said.