New Haven's expansion continued during the two World Wars, with most new inhabitants being African Americans from the American South and Puerto Ricans. The city reached its peak population after World War II. The area of New Haven is only , encouraging further development of new housing after 1950 in adjacent, suburban towns. Moreover, as in other U.S. cities in the 1950s, New Haven began to suffer white flight of middle-class workers. One author suggested that aggressive redlining and rezoning made it difficult for residents to obtain financing for older, deteriorating urban housing stock, thereby condemning such structures to deterioration.