# Why California school data is missing, suppressed, or marked N/A Learn why a California school value can be blank or N/A, including privacy rules, grade limits, reporting delays, and record matching. 4 min read Updated: 2026-09-28 Zero is a reported value. A blank or N/A means California School Trends has no public number it can safely display for that school, year, subject, or student group. ## Small-group results are hidden for privacy California hides some test statistics when fewer than 11 students are included. This often affects small schools and results for English learners, students with disabilities, or low-income students. A school may enroll students in one of those groups even when its public test table shows N/A. The state may also hide related totals if they could reveal the protected result. ## The test may not apply to the school California's statewide reading and math tests are given in grades 3 through 8 and grade 11. A school serving only kindergarten through grade 2 will not have a result for those tests. A high school's result usually comes from grade 11 rather than the entire student body. ## Public files arrive at different times Assessment, enrollment, staffing, finance, and school directory data are published separately. A page may show a newer year for test results than for staffing or finance. New schools can appear in the state directory before they have a year of test results. Closed or reorganized schools may have older records but no current value. California School Trends leaves unavailable values blank so they do not change averages, trends, or rankings. ## How missing results affect rankings A school needs a public result to enter a ranking for that subject and year. A school with no public reading result is left out of the reading ranking. The number of ranked schools can therefore differ between reading and math or change from one year to the next. ## When to report a missing value If the original state source shows a value that is missing from California School Trends, report the page. That may indicate a record-matching or update problem rather than a state suppression rule. ## Sources and method - [California Department of Education: CAASPP research file layout](https://www.cde.ca.gov/ta/tg/ca/caaresearchlayout.asp) - [California CAASPP technical report](https://www.cde.ca.gov/ta/tg/ca/documents/sbac18techrpt.pdf) - [California School Trends data sources](https://caschooltrends.com/data-sources) ## Keep exploring **Data methods** See why school values are blank or N/A and how missing results affect public comparisons. [See this topic](/learn/school-data-methodology) [Browse all guides](/learn)