The coronavirus pandemic is slamming the U.S. casual-dining sector, as companies including Darden Restaurants Inc., the owner of Olive Garden and other chains, race to switch to takeout service.

Darden, the largest casual dining chain in the U.S. with eight brands and 1,800 restaurants, said Thursday that same-store sales across its restaurants plunged 20.6% for the week ending March 15, as more coronavirus cases appeared domestically. Sales in the Orlando, Fla.-based company’s fine-dining business fell further.

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