segregation and Jim Crow. Between 1910 and 1970, the black population of Houston ranged from 21% to 32.7%. They were virtually without political representation until after 1965 and passage of the federal Voting Rights Act, which enforced their constitutional rights of suffrage. Many blacks left Houston for the West Coast during and after World War II in the Great Migration, as jobs increased rapidly in the defense industry on that coast and social conditions were better. In 1970, 90% of the black people in Houston lived in predominantly African-American neighborhoods, reflecting decades of legal, residential segregation. By 1980 there was some increase in diversity in the city, and 82% of blacks lived in majority-black areas. Since the late 20th century, with changes in social conditions and the burgeoning Houston economy, there has been an increasing New Great Migration of blacks to the South. Many are college educated and have moved to Houston for its lower cost of living and job opportunities compared to some northern and western cities. Many of the new professional migrants settle directly in the suburbs, which offer more housing than the city; among them are upper class, majority-black neighborhoods. Black Enterprise has referred to Houston as the next black mecca. Houston is ranked among the best U.S. metros for Black professionals. In 2010 Strait and Gong stated that of all ethnic groups in Houston, African Americans were the most segregated from non-Hispanic whites. African immigrants A significant number of African immigrants have made the Houston area home. As of 2003 Houston does not have as many African immigrants as Hispanic and Asian immigrants. The African immigrants in Houston have higher education levels than other immigrant groups and US-born whites. According to Stephen Klineberg, a sociology professor at Rice University, as of 2003, almost 35% of African immigrants have university degrees, and 28% of African immigrants have postgraduate degrees. In the Houston area, 28% of US-born Whites have university degrees, and 16% have postgraduate degrees. In 2012, the total trade between Houston and Africa was $19.7 billion. Houston is Africa's largest U.S. trade partner. In 2016 the city had about 60,000 people of recent African immigrant origin. In 2019 Ethiopian Airlines CEO Tewolde GebreMariam stated that the presence of African immigrants in United States is one reason related to the airline's decision to establish the Bush Intercontinental Airport-Lome Airport route. Nigerians Charles W. Corey of the U.S.