The historical roots of Florida's current growth management system trace back to the efforts of a poor, sparsely populated pioneer state that strained to promote population and economic growth. In 1850, Florida's population was 87,445. By 1900 it had expanded to 528,542 and the 1950 census counted 2.7 million Floridians. From 1950 to the present, Florida has been in the midst of explosive economic and population expansion. The population counts by decade showed 4.9 million in 1960; 6.7 million in 1970; 9.7 million in 1980; and over 12.0 million in 1988. Strong population increases, fueled by immigration from the Northeast, Midwest and other parts of the South, are likely to continue. Current estimates project an annual increase of over 300,000, or about 3,000,000 each decade. Florida is now the fourth largest state in the nation, exceeded in population only by Texas, New York, and California. Some project the state to be third in population at the turn of the century, with 15 to 16 million people. Between 2020 and 2030, one projection shows Florida with 22 million people, or double the state's 1986 population.