their families to afford comfortable single family housing in suburbs. The manufacturing industry has historically been a base for the prosperity of major cities. When these industries relocate to larger, less urban environments, some cities have experienced population loss with associated urban decay, and even riots. Cutbacks on police and fire services may result, while lobbying for government funded housing may increase. Increased city taxes encourage residents to move out. Libertarian economists argue that rent control contributes to urban blight by reducing new construction and investment in housing and disincentivizing maintenance. Countries United States Historically in the United States, the white middle class gradually left the cities for suburban areas due to African-American migration north toward cities after World War I. American cities often declare blighted status once determined that urban renewal strategies are the most appropriate means to encourage the private investment for reversing deteriorating downtown conditions. Some historians differentiate between the first Great Migration (1910–1930), numbering about 1.6 million African-American migrants who left mostly Southern rural areas to migrate to northern and Midwestern industrial cities, and, after a lull during the Great Depression, a Second Great Migration (1940–1970), in which 5 million or more African-Americans moved, including many to California and various western cities. Between 1910 and 1970, African-Americans moved from southern States, especially Alabama, Louisiana, Mississippi, and Texas to other regions of the United States, many of them townspeople with urban skills. By the end of the Second Great Migration, African-Americans had become an urbanized population, with more than 80% of Black Americans living in cities. A majority of 53 percent remained in the South, while 40 percent lived in the Northeast and Midwest and 7 percent in the West. From the 1930s until 1977, African-Americans seeking borrowed capital for housing and businesses were discriminated against via the federal-government–legislated discriminatory lending practices for the Federal Housing Administration (FHA) via redlining. In 1977, the US Congress passed the Community Reinvestment Act, designed to encourage commercial banks and savings associations to help meet the needs of borrowers in all segments of their communities, including low- and moderate-income neighborhoods. Later urban centers were drained further through the advent of mass car ownership, the marketing of suburbia as a location to move to, and the building of the Interstate Highway System. In North America, this shift manifested itself in strip malls, suburban retail and employment centers, and very low-density housing estates.