Scores Given in Comparison With National 50th Percentile

This year The Times is publishing school results for the statewide Stanford 9 tests as the percentages of students at or above the 50th percentile ranks, which are the national averages for specific test subjects and grades.

Previously, The Times published schools’ mean percentile ranks, which are schools’ rankings in comparison with those of other schools nationwide.

The California Department of Education provides three other measures to choose from as well. Each measure has advantages and disadvantages, but most education experts recommend using the percentage of students at or above the 50th percentile. That is the score used by the state in its year-to-year comparisons.

In practice, the figures for the percentages at or above the national averages and for mean percentile ranks are usually closely matched, according to comparisons The Times made of the two scores.