NEW YORK - (AP) - City Comptroller John Liu has flunked the NewYork City Department of Education's high school grading system.

Liu charged in a new audit that education officials have revisedthe complex formula used to grade schools every year, which makesit difficult to get a true picture of a school's yearly progress.

Liu says the system used to decide school closings "leavesteachers and students confused about what they need to improve."

The audit focused on 10 schools representing the five boroughs.

In a statement to the New York Post, the Department of Educationsays progress reports are "a one-year snapshot that is designed tocompare schools based on their performance and progress during thatschool year."