The rise in the popularity of passive investment strategies, coupled with pending regulatory changes in Europe, is shaking the U.S. asset management industry, according to a study published on Monday by New York City-based TABB Group,

The ongoing shift from active investment strategies to passive, index-based products “has the industry on edge,” the research and consulting firm says in a statement.

The firm reports that almost US$3 trillion has moved from active funds to passive products in the U.S. over the past 10 years. Its study, which canvassed 95 head and senior traders at U.S. equity asset managers and hedge funds, finds that over 95% of U.S. equity funds have been impacted by investors’ move from active to passive strategies, and that “a considerable number of managers both large and small do not have a strategy to counter this trend.”

Indeed, the firm says that 35% are simply hoping that the trend changes. Other firms are working to reduce their cost structure, among a variety of other strategies.

Additionally, the study finds that forthcoming new rules in Europe to encourage the unbundling of trading commissions and investment research will also impact most U.S. asset managers. It notes that 76% of U.S. managers now expect to be impacted by the European unbundling rules, up from 66% a year ago.

“Virtually all larger funds will need to restructure the way they procure research,” says Valerie Bogard, TABB Group analyst, in a statement. “Larger funds are more impacted and more prepared than smaller funds. Many smaller funds have not even started analyzing the impact of unbundling on their business.”

“The combination of the move toward passive investing, unbundling, and low volatility has the U.S. equity institutional investor commission pool down 7.5% from 2015,” she adds.