Principals who worried that new, toughened state math and English exams would hurt their performance reviews had good reason: Far fewer principals earned high marks from the city last year.

Data on principals’ performance ratings, which GothamSchools obtained through a Freedom of Information Law request, show that the number of principals who “substantially exceed” expectations fell by roughly 60 percent from 2009 to 2010. (A full list of all principals and how they scored is at the end of this post.)

The decrease parallels a drop in test scores and fewer schools earning “A” grades on their progress reports. The percentage of elementary and middle schools to get A’s on their city-issued report cards fell from 84 to 25 percent — a drop precipitated by more students failing the exams and the city grading schools on a curve.

With fewer principals earning the city’s highest rating, more fell into the middle. Principals can earn one of five ratings: does not meet expectations, partially meets, meets, exceeds, or substantially exceeds. The number of principals rated as “exceeding” expectations rose from 465 to 608 and the number who “meet” expectations climbed from 114 to 376.

The number of principals earning substandard marks also rose. In 2009, only five principals were rated “does not meet” expectations, but that number more than quadrupled to 21 in 2010. Even with the increase, the percentage of principals earning the lowest rating is now only 1.4 percent of the 1449 on the city’s list.

Last year’s principal ratings breakdown more closely resembled 2008’s, the first conducted according to the current principal evaluation formula.

Every year, several dozen principals do not receive ratings either because they retired, are brand new, or were removed. Also, principals who appealed their rankings are not included on the list the department released because their evaluations were not final. For example, Janet Saraceno, principal of Lehman High School, where GothamSchools revealed that student grades had been altered to boost the school’s graduation rate, does not appear on the list the department released.

As with school progress reports, much of a principal’s rating is determined by test scores.

The formula bases 32 percent of a principal’s annual “grade” on his school’s progress report score, 22 percent on the Quality Review grade, 10 percent on legal compliance, and 5 percent on offering special education services. The remaining 31 percent of the Principal Performance Review grade is based on whether principals have met the “goals and objectives” they set out for themselves — goals that officials say are best when they relate to student achievement. The formula means that a principal at a school where test scores are increasing is virtually assured of a passing evaluation, no matter what teachers, parents, or the community superintendent thinks.

Some of the lowest-rated principals last year have already left their positions, although it is not clear whether their evaluations contributed to their departures. Ira Weston at Paul Robeson High School and Jose Maldonado-Rivera at the Columbia Secondary School both received “does not meet” ratings, but the city cited other reasons for removing them from their positions. A department official said the city considers the ratings along with other information in deciding whether a principal keeps his job.