The nation's current account balance was in the black for the fourth straight month in May, standing at ¥522.8 billion, as imports slid for the first time in 19 months after the April 1 consumption tax hike cooled domestic demand, the government said Tuesday.

But the surplus in the balance — one of the widest gauges of international trade for a country — fell 7.7 percent from a year earlier as the slowing pace of the yen's depreciation dampened growth in the income surplus, the Finance Ministry said in a preliminary report.

Imports declined 0.4 percent from the same month last year to ¥6.395 trillion against a backdrop of falling imports of crude oil, while exports climbed for the 15th consecutive month, up 2.0 percent on year to ¥5.719 trillion, on the back of an expansion in shipments of metalworking machines.