From the brief: "Mathematica, in partnership with the Pennsylvania Department of Education, predicted spring 2021 proficiency for nearly all students in grades 5–8, accounting for the unique assessment issues that year. The findings revealed that steep declines in proficiency likely occurred from 2019 to 2021, larger than data suggested from test takers only. By spring 2022, proficiency rates in grades 5–8 had regained 6 points of their 10-point drop in ELA and nearly 5 points of their 13-point drop in math."