The adjacent table reflects major decreases in population from 1910 to 1920, and from 1940 to 1960. These were periods of the Great Migration from the South by African Americans, who first moved to jobs in industrial cities in the North and Midwest. In the 1940s and after, they moved to the West Coast for jobs in the rapidly growing defense industry. Farm work declined with mechanization of agriculture. But blacks also migrated to escape the violence and social repression of Mississippi, where they had been essentially disenfranchised since 1890 and lived under Jim Crow laws and the threat of violence; the state had a high rate of lynchings.