Study: U.S. wealth inequality worse than previously thought by Tom Huddleston, Jr. @FortuneMagazine July 15, 2014, 12:04 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons A new study from the European Central Bank suggests that the state of wealth inequality in the U.S. is even more dire than previous statistics have shown. America’s wealthiest 1% likely holds between 35% and 37% of the nation’s wealth, the highest rate out of all 10 wealthy countries examined, according to a working paper authored by ECB senior economist Philip Vermeulen. That range, which outpaces the 34% Federal Reserve figure often cited for the U.S., incorporates data from what Vermeulen calls the “missing rich”—billionaires whose massive wealth he claims is underestimated by most other surveys. Taking into account the fact that wealthier households tend to have lower response rates to surveys that seek to calculate their wealth, as opposed to less affluent respondents, Vermeulen’s paper attempts to fill those gaps by incorporating data from a variety of surveys and sources, including Forbes’ billionaires list. Vermeulen notes that wealth distribution calculations are far from foolproof. “The results clearly indicate that survey wealth estimates are very likely to underestimate wealth at the top,” he writes. He also adds that his tweaks regarding U.S. wealth inequality represent only “a marginal increase,” but his study found similar increases in wealth gaps within other countries when compared to other similar studies. In the Netherlands, for example, overall wealth held by that country’s top 1% of households increases as much as eight percentage points under Vermeulen’s method, from 9% to as much as 17%. And countries such as France and Spain also see increases of one or two percentage points, according to the ECB study.