Complex sentence: In 1970, Vigor High School on Wilson Avenue, which had been Prichard's white high school during segregation was 70% white, by 1980, it was 80% black, even considering that most of Prichard's remaining white areas were in its district.
Split into simpler sentences: In 1970, Vigor High School on Wilson Avenue, which had been Prichard's white high school during segregation was 70% white. By 1980, it was 80% black, even considering that most of Prichard's remaining white areas were in its district.