Aeon Co. reported that net profit plunged 91.4 percent to ¥2.02 billion in the first half of the business year as weak consumer spending after the April consumption tax hike hurt the giant retailer's mainstay supermarket business.

The nation's biggest retail chain also said Friday that group operating profit from March to August sank 41.2 percent from a year ago to ¥43.37 billion after it bungled its response to the tax hike.

"We mismanaged our battle after the tax increase," Aeon President Motoya Okada told reporters.

Household spending remains sluggish after the government raised the consumption tax to 8 percent from 5 percent on April 1. Unstable weather also eroded Aeon's summer sales.

The group's operating revenue was up 15.1 percent at ¥3.43 trillion.

Aeon maintained its full-year profit forecast, projecting an operating profit of between ¥200 billion and ¥210 billion and a net profit of ¥48 billion.

Rival retail giant Seven & i Holdings Co. reported Thursday that group operating profit from March to August rose 1.6 percent year on year to ¥167.23 billion, the highest ever for that period, on brisk convenience store earnings despite the tax hike.