NEW YORK—The number of institutional investors committed to cutting fossil fuel stocks from their portfolios has risen from 180 in 2014 to more than 1,100 now, as activists turn up the heat on companies over climate change.

The number of fossil fuel divestments have risen dramatically since the 2015 Paris agreement on combating climate change. In 2014, investors with a total $52bn in assets under management had agreed to shed their fossil fuel holdings. Now that group represents more than $11 trillion in total assets, according to a report from 350.org, an environmental organization advocating for divestment. More than 900 additional investors, including asset managers, pensions and insurers, have pledged to divest since the year before the Paris accord.

Read: Divestment Movement To Oil And Gas Industry: Drop Dead

There has been a shift in the way people think about their investments’ impact, especially after the Paris agreement, said Ahmed Mokgopo, a divestment campaigner at 350.org and co-author of the report. “The divestment campaign started to question the moral legitimacy of the fossil fuel companies and we’ve definitely achieved that,” he said.

There is strong evidence that its efforts are having an effect. Royal Dutch Shell listed divestment campaigns as a material risk in its latest annual report. Similarly, BP CEO Bob Dudley said in 2018 that these activists’ efforts could threaten energy security and the global economy. However, it is not clear how much money has been divested and what tangible financial impact the campaign has had.

The headline figure of $11 trillion represents the total assets of the investors pledging to divest — not the money specifically being pulled from fossil fuel companies. For example, Norway’s $1 trillion sovereign wealth fund is fully counted in that total, not just the $7.5 billion they agreed to pull from oil and gas companies earlier this year, said Yossi Cadan, global finance campaign manager at 350.org. Further complicating matters, 350.org is not able to track up-to-date outflows since divestment can be a drawn-out process that often takes years to complete.

However, the investors making public declarations are not the only ones exiting the industry. “Most investors are shy . . . there is a lot more divestment going on than even that report shows,” said Kathy Hipple, financial analyst at the Institute for Energy Economics and Financial Analysis.

Energy has been the worst performing sector in the S&P 500 in recent years, so it has paid to avoid fossil fuel stocks, she said, noting that oil and gas companies now account for just 4.4% of the S&P 500, while in 1980 they represented more than 28% of the index.

Some investors, such as Japan’s $1.3 trillion national pension fund, believe it is better to stay invested and push companies to change their business practices. But that engagement-oriented approach also has its limits, especially when the company’s primary business model is the issue at hand. “You’re not going to engage a fossil fuel company or a tobacco company out of being a fossil fuel or tobacco company,” said Craig Metrick, managing director at investment adviser Cornerstone Capital Group.

If activists are seeking the demise of the industry, people will need to stop using fossil fuels—and neither engagement or divestment will achieve that goal, said Julie Gorte, senior vice president of sustainable investing at Impax Asset Management. While it is getting easier to power buildings with renewables or to use electric vehicles, there is no alternative to fossil fuels for flying or shipping, she pointed out. “As long as there is a market for fossil fuels, someone will invest in them.”