1998? I wanted a quarter century of Grade 8 and that gives me 1998 to 2024 with NAEP. 2000 reading assessment was Grade 4 only. You can do it with any pair of years.
Does this correlate with the racial proportion data?
It is wrong to get overly exact here though. We are talking about a overall score variance of just 10pts in the face of an achievement gap of nearly 30pts, with an absolutely massive 20% decline in white population share over the 26 year period.