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Fifty years ago, Americans watched on their TV sets as state troopers and local law enforcement attacked nonviolent civil rights marchers in Selma, Alabama. The event, known afterwards as “Bloody Sunday,” helped spur the passage of the Voting Rights Act. This weekend, President Obama visits Selma to commemorate the 50th anniversary of Bloody Sunday, which happened on March 7, 1965.

Since then, the U.S. has made big strides toward equal rights, with the passage of the Voting Rights Act, the abolishment of Jim Crow laws, and the appointment of many more African Americans to political office. But significant gaps remain, and in some ways gaps between blacks and whites have even widened over the past few decades, as data from Pew Research Center show.

Specifically, gaps in high school completion, life expectancy at birth and voter turnout have all narrowed, with blacks actually surpassing whites in the last category.

However, the difference in the percentage of whites and blacks above the poverty line and the gap between home ownership among whites and blacks have not changed much since the 1970s.

Most disturbingly, African-Americans are actually falling farther behind in some respects. The gaps between whites and blacks have widened for three important categories: median household income, the marriage rate and median household wealth.

50 years after the Civil Rights movement, there's little room for complacency. Even in Selma itself, more than 40 percent of the population lives in poverty and the unemployment rate is twice the state average, and the town is still struggling to overcome its racial divisions.

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