NASHVILLE (AP) — A new study shows Tennessee is among 11 states in which charter school performance has outpaced traditional public school growth in both mathematics and reading.

The study is by the independent Center for Research on Education Outcomes at Stanford University. It evaluated charter school performance in 26 states and New York City.

Tennessee's charter school students, in comparison to their traditional public school counterparts, were found to gain the equivalent of an additional 86 days of learning in reading and 72 days in mathematics.

Tennessee is tied with Rhode Island among states studied for the highest growth in reading.

This fall, Tennessee is expected to have about 70 charter schools serving more than 16,500 students.