A national group that investigates what it deems corruption that undermines democracy is calling attention to the high rate of charter school closures in Florida.The Wisconsin-based Center for Media and Democracy has issued data showing that since 2000, 491 of 1,091 Florida charter schools have closed their doors. That's 38 percent, which is 7 points higher than the national average.The Florida Department of Education shows 389 charters have closed, not 491. Officials noted that at least 40 of the schools merged and did not shut down."For example, The Villages Charter School in Sumter County used to be three separate schools (elementary, middle, high). They merged into a single K-12, and two the school numbers were inactivated and now show as closed," department spokeswoman Cheryl Etters said via email.Center researcher David Armiak called the rate of closures "alarming," and said it raises concerns about the performance and accountability of charters, which operate with state funding but do not follow all the same laws as district schools.Charter school supporters have said the charters are held accountable, in that they can be forced to close if they earn a D or F in state grading for two consecutive years. Charter school students take the same state tests as students in district schools.The Center observed that the closures disproportionately affected minority students. Forty-seven percent of students in the closed schools were black, while more than half qualified for free and reduced-price meals.The Center has raised several questions in the past about charter schools and how they might be used as a method to subvert traditional public education. In 2017, it wrote about how the federal government continued to pour millions of dollars into the "charter school black hole" in Florida and other states.NOTE: This post has been updated to reflect additional information provided by the Florida Department of Education.