Americans with non-retirement investment accounts are for the most part unaware of main investing concepts, and many have little idea of the fees they’re paying, according to a new report.

Two-thirds of U.S. adults with taxable investment accounts incorrectly answered more than half of the questions on a 10-question investor knowledge quiz put out by Finra, the industry’s self-regulator says.

The questions ranged from basic attributes of stocks and bonds to the connection between risk and returns and the basics of trading on margin and short-selling. Forty-six percent of respondents, for example, believe that past performance is a good indicator of future results and only 30% understand that the benefits of index funds over actively managed funds are their generally lower fees, according to a survey of around 2,000 U.S. adults who said that they have investments in retirement accounts, such as 401(k)s and IRAs, and most of whom also have non-retirement accounts, according to Finra.

Furthermore, close to a third of investors believe they’re not paying any fees or expenses for their investment accounts, or don’t know know how much they’re paying, the regulator found. And only 7% have used BrokerCheck and only 9% have used, according to the report.

At the same time, 75% of investors believe they have access to enough information to make investment decisions, the survey found.

Forty-six percent of the investors surveyed say they rely on free online services, websites and blogs, while 42% get their information from newspapers, magazines and books and 17% get investment information from social media, according to Finra.

“These research findings underscore the need for researchers, policymakers, advocates and industry stakeholders to continue to develop innovative investor tools and resources to better educate investors and to help protect them from fraud,” Gerri Walsh, president of the Finra Foundation and Finra’s senior vice president for investor education, says in a statement.