FILE: Pre-kindergarten children attend classes at LEAP Academy Early Childhood School at KIPP DC. KIPP is a national network of public charter schools. (Astrid Riecken/For The Washington Post)

New Orleans led the nation last year as the city with the greatest percentage of students enrolled in public charter schools, followed by Detroit and the District of Columbia, according to a new survey released Tuesday by the National Alliance for Public Charter Schools.

According to the non-profit organization, 79 percent of public school students in New Orleans attended charters in the last school year, followed by 51 percent in Detroit, 43 percent in D.C., 36 percent each in Flint, Mich. and Kansas City, Mo. and 35 percent in Gary, Ind.

The school district with the largest number of students enrolled in public charter schools was Los Angeles, where more than 120,000 students attended charters. L.A. was followed by New York, Philadelphia, Detroit and Chicago, the survey found.

Hall County, Ga., which includes the city of Gainesville, led the nation in terms of the highest growth of charter students, largely because three traditional schools converted to charters, according to the alliance. Hall County was followed by San Diego; Duval County, Fla.; Newark, N.J. and Hillsborough County, Fla., the survey found.

Charters are public schools that are funded through tax dollars but are run independently from the centralized school system. Some are run by non-profit managers; others are operated by for-profit companies. Most are not unionized.

The number of school districts where charters make up at least 20 percent of the schools has climbed from six in 2005-2006 to 32 in 2012-2013, according to the alliance.

An analysis of the locations of charter schools showed that communities with high concentrations of public charter students tended to be in the Midwest and Northeast.