Warren Buffett plans to wait until around April 1 to decide whether the coronavirus pandemic will require changes to Berkshire Hathaway Inc’s annual shareholder weekend a month later, Omaha, Nebraska’s mayor Jean Stothert said.

The pandemic appears increasingly likely to disrupt a three-day weekend that Buffett, who is Berkshire‘s chairman and among the world’s most revered investors, calls Woodstock for Capitalists and is corporate America’s largest gathering.

Speaking at a news conference to discuss the outbreak’s impact on Omaha, Stothert said Buffett called her on Monday night and said his “preference” was to wait until a month before the May 1-3 weekend to evaluate the situation and recommendations of health and other public officials.

The weekend includes Berkshire‘s May 2 annual meeting.

“He said that, he’s a very responsible person, and public safety is a priority for him,” Stothert said.

Buffett’s assistant did not respond to requests for comment.

The World Health Organization on Wednesday declared the coronavirus outbreak a pandemic.

A day earlier, in a Yahoo Finance interview, Buffett called the outbreak and plunging oil prices “a big one-two punch” for markets, but less severe than the “panic” during the 1987 stock market crash and 2008 financial crisis.

Berkshire‘s shareholder weekend typically attracts 40,000 or more people to Omaha, including 5,000 from China, where the outbreak began.

Events that normally draw large crowds include the annual meeting, a cocktail reception, a picnic, a 5-kilometer (3.1-mile) run, and shopping discounts.

Buffett, 89, routinely mingles with shareholders and fans, sometimes with a horde of reporters, photographers and TV staff in close proximity.

The meeting features Buffett and Berkshire Vice Chairman Charlie Munger, 96, answering several hours of shareholder questions, in an arena that holds close to 19,000 people and normally fills to capacity.

Health experts consider elderly people the most at risk of dying from the coronavirus.

The meeting is to be live-streamed by Yahoo Finance, and Berkshire said last week it will occur “irrespective of conditions at that time,” but other events may be changed.

Many companies are moving annual meetings online to help contain the outbreak, and a growing number of countries and cities worldwide have banned large-scale events.

Hotels in downtown Omaha normally sell out nearly a year in advance for Berkshire‘s weekend, but a handful that were fully booked in February now have vacancies.

Within Omaha, the outbreak caused the scrapping of this weekend’s baseball series between Creighton University and Central Connecticut State University, and may affect the College World Series of baseball scheduled for June 13 to 24.