This post originally appeared on Data Quality Campaign’s The Flashlight blog.

Today the Data Quality Campaign released Empowering Parents and Communities through Public Reporting, a primer that provides important context for why public reporting about student opportunity and achievement matters. The brief highlights both the value that reporting adds and the shortcomings of many current efforts. But one flaw is especially crucial to underscore: Even as more states provide data beyond the basics required by the federal government, they often fail to break the data out for different groups of students. That’s especially true of measures of college and career readiness.

If a data point is important enough to be publicly reported, it needs to be disaggregated. Otherwise, conversations about a school or district’s performance — and about how to help it improve — won’t be able to spark real change. Why? Repeatedly, districtwide or schoolwide averages mask differences in opportunity and achievement.

Take a high school in New Jersey, where about two-thirds of students are white and about one-quarter are Latino. Overall, about 80 percent of its graduates enroll in college. But dig under that average, and we see that nearly 90 percent of white graduates, but just half of Latino graduates, enroll in college. Or take a Texas high school — half Latino and about 20 percent each African American and white. While more than three in four white graduates at the school are considered “college ready” in both English and math, less than two in four African American or Latino graduates meet that benchmark.

To be clear, these states should be commended for making disaggregated information on achievement and opportunity available. It’s only because they have already done so that we can identify these types of gaps — gaps which, unfortunately, are far too common. Other states should follow their lead in making this sort of information publicly available — to unearth hard realities and allow schools and communities to have tough but necessary conversations.

Public reporting will never tell us everything we need to know about a school or its students, but it’s important for identifying patterns within a school. And it’s crucial for ensuring that parents, educators, and policymakers are paying explicit attention to all groups of students, providing them the experiences and opportunities that will help them soar.