How did the ratio of voter registration rates change between african americans and whites as a result of the voting rights act of 1965?

African American voter registration rates surpassed white registration rates.

While African-Americans were 'Free' people after the Civil War, state-level restrictions including the Jim Crow Laws had made it difficult and even impossible for most African-Americans to register to vote.

As such, the community virtually had no representation.

After Lyndon Johnson's voting rights act of 1965, the State government could no longer restrict African-Americans from voting.

Within just a couple of years, the African-American community became powerful enough that politicians started to rally support among them.

An extreme sample is that of Mississippi, a State with 40% African American population but only 6% of them registered to vote. By 1967, 59.89% of these African-Americans were registered to vote in the State.

The largest African-American population was in States such as as Alabama, Georgia, North Carolina, South Carolina, Virginia etc.

Before 1965 less than 30% of African-Americans had registered to vote. By 1967 more than 55% of them had the right to vote.