Short answer: We do not have a fair, exact percentage comparing how many U.S. high school graduates could read proficiently in 1970 with how many can today. The tests and measurements are not the same.
What we can compare
- Graduation: Roughly 77 out of every 100 students graduated from high school around 1970. In recent years, about 87 out of every 100 students graduated. These are estimates, and the way graduation is counted has changed.
- Reading today: On the 2024 national reading test, about 35 out of every 100 U.S. 12th graders scored at or above the test’s “Proficient” level. This means they showed solid understanding of the reading tasks on that test.
Why the reading comparison is tricky
The modern national test for 12th graders was not given in 1970. A different national reading test began around that time, but it tested 17-year-olds—not specifically students who were graduating—and its results cannot be turned into the same “Proficient” percentage used today.
Also, “Proficient” is a test category. A student below that level may still be able to read; it does not mean the student cannot read at all.
Bottom line
More students graduate from high school today than around 1970, based on commonly reported estimates. But we cannot reliably say whether a larger or smaller share of graduates could read proficiently, because there is no matching reading test for the two years.
In simple terms: We can compare graduation estimates, and we can report today’s reading-test result, but we should not pretend those numbers make a direct 1970-versus-today reading comparison.