Roughly 6 percent of city teachers were deemed ineffective last year based solely on their students’ scores on state math and reading tests, new city data shows.

The data stemmed from a trial run of just one segment of a new teacher evaluation system that will be implemented at city public schools in the fall.

That segment, which only looks at state math or reading scores for students in grades 4 to 8, will only count for 20 percent of a teacher’s overall performance rating in 2013-14.

Local assessments and principal observations will count for the remaining 80 percent of teachers’ ratings.