A club of more than 800 multimillionaire investors is hoarding cash at unprecedented levels, according to a recent article in Bloomberg.

Tiger 21—whose members typically have more than $100 million in assets—has reportedly raised its cash holdings to 19% of total assets due to “concerns over the economic consequences of the Covid pandemic in the U.S.,” up from about 12% since the start of the crisis. About a quarter of the group’s members say they expect the crisis to continue until the end of next June, the article reports.

According to the club’s chairman, Michael Sonnenfeldt, the shift is “the largest, fastest change in asset allocation Tiger 21 has seen. He explains, “In trying to build resources prudently, members have gained liquidity and will not immediately reinvest in those areas in order to keep and build cash to weather this storm.”

Most Tiger 21 members, who usually meet monthly to “share perspectives and debate investments,” expect the virus crisis to continue for the rest of this year, but their report says they remain confident in long-term U.S. growth and are still looking for “dramatic upside opportunity.”