(Bloomberg) -- Investors who piled into ESG stock strategies have beat broader indexes this year, fueling speculation that the strategy of prioritizing companies doing social good will continue to gain adherents well after the current crisis passes.

Most exchange-traded funds focused on companies with above-average marks for environmental, social and governance practices have outperformed this year, according to research from Bloomberg Intelligence. So far in 2020, 59% of U.S. ESG ETFs are doing better than the S&P 500 Index while 60% of European ESG ETFs have beat the MSCI Europe Index.

The results are a boon for investors who piled into ESG funds in the final few months of the longest bull market in history. Sustainable ETFs added more than $8 billion in 2019, quadruple the previous year, and another $4 billion in January. The idea of conscientious investing also got a boost as BlackRock’s Larry Fink pledged to put climate at the center of his firm’s ethos. With the strategy proving prescient as the S&P 500 swooned more than 30% amid the coronavirus panic, analysts say it’s likely to gain in popularity.

“The advantage of ESG companies right now is a perception that they are more likely to take a stakeholder view of their business as opposed to a purely shareholder view of their business,” said Dan Russo, chief market strategist at Chaikin Analytics. “Investors are starting to look to the other side of this initial coronavirus situation and maybe looking for the companies that did right by their employees, that did right by their supply chain.”

On a sector neutral basis, companies with better ESG risk profiles have outperformed those with worse ESG risk profiles since the S&P 500 peaked on Feb. 19, according to analysts at RBC Capital Markets.

ESG ETFs took in $1.5 billion in March, bringing total assets for the sector to $19.1 billion, down from its peak of $20.8 billion in February but still higher than at any point in 2019.

There are still some signs of trouble in the do-good universe. Six of the 10 largest ESG-focused U.S. mutual funds have underperformed the S&P 500 this year, with the Parnassus Endeavor Fund, for example, down 23% this year compared with a 19% drop for the S&P 500.

But researchers at Bloomberg Intelligence predict that resilience in ESG ETF performance will serve as a catalyst for further demand.

Matt Maley, a strategist at Miller Tabak & Co., agrees.

“It’s investors thinking, we need to do things that are better for everybody, for the whole world, so I’m going to support the companies that are going to help us do that,” Maley said. “People come together in a crisis.”

©2020 Bloomberg L.P.