Restaurant sales across Japan plunged 17.3 percent in March from a year earlier, the sharpest drop in nearly 30 years, as the coronavirus outbreak continues to take its toll, an industry body reported.

It was the first decline in five months and the pace of slide was the fastest since comparable data was first collated in January 1994, the Japan Food Service Association said Monday.

This month is expected to be worse with the government having declared a state of emergency, asking people to avoid nonessential outings and some businesses to close. Restaurants have been requested to shorten their operating hours.

"The restaurant industry is in dire straits as we don't expect to see the usual number of customers," the association said.

Sales fell in all categories of restaurants, with bars and izakaya (Japanese pubs) marking a 43.3 percent fall.

Restaurants normally see strong sales in March, the final month of the fiscal and academic year and a traditional time for farewell and other parties. But this year, many were canceled due to coronavirus worries.