The 2019 Best High School Rankings results, released April 30 by the U.S. News and World Report, showed Diamond Bar High School ranking 542nd in the nation, dropping in ranking in the last few years, from 277th in 2017 and 375th in 2018. But part of the reason for the decline may be the greater number of schools being ranked.

The online magazine revised its previous ranking methodology and utilized the new regimen for the first time this year, which U.S. claims improved on multiple aspects of its evaluation, improving the accuracy of its results and helping users better understand the basis of the system.

Expanding its area coverage by more than seven times, U.S. News classified more than 17,245 schools out of the 23,000 they reviewed, compared to the 2,700 schools it ranked last year.

Introducing a mass of new schools to the already existing bracket drastically shifted many of the previously established rankings.

Among California schools, DBHS ranked 76th, while Walnut High School followed, placing 99th in the state and 704th nationally. Nearby Troy High School ranked 35th in state and 278th in the country.

Amidst the numerous schools ranked, Whitney High School was ranked 1st in the state, followed by Oxford Academy, Dr. J.T. Owens Gilroy Early College Academy, Pacific Collegiate Charter, and many more.

On June 12, U.S. News announced the first-ever metropolitan area rankings in Phase 2. DBHS ranked 26th in Los Angeles.

Previously, schools were deemed ineligible if they did not meet the minimum requirements for state assessments or graduation rates, which caused more than half the schools originally gathered to be eliminated from consideration.

The high schools were also measured on AP and IB exam participation and performance, therefore prompting the expulsion of schools that do not offer such programs or lack sufficient numbers of participants, even if the schools excel in the other aspects of the inspection.

In past years, U.S. News received numerous complaints on the lack of clarity in its labyrinthine filtering process. The U.S. News utilized a new system that aggregates a school’s overall score, or the percentile a school ranked nationally.

There are six elements to gauging a school’s overall score including college readiness, college curriculum breadth, math and reading proficiency, math and reading performance, underserved student performance and graduation rate.

Making up the largest percentage in the weight of the general score, college readiness and curriculum breadth is defined as the proportion of a school’s seniors who took and passed AP or IB exams.

Meanwhile, math and reading proficiency relate to the students’ state assessment scores in math and reading, while the math and reading performance is based on the total assessment of scores compared to the predicted demographics, according to the magazine.

Furthermore, underserved student performance pertains to the learning outcomes of students of African American or Latino ethnicity, as well as low-income students.  

U.S. News evaluated the performance of these participants along with the performance of the non-underserved students.

Finally, another factor is graduation rate, which is the measure of the portion of students who graduated after receiving four years of education at a school.

Additional information was added to this story after it was first published.