 By July 1908, Springfield's population was over 45,000 (of which about 40 percent were under the age of 21).Of those 45,000, nearly 6,500 were European immigrants, who together with their first generation American offspring accounted for 40 percent of Springfield's population, while native white Americans made up just under 55 percent and blacks about 6 percent.These population shifts had economic, political and social implications, particularly as the unemployment rate increased from under 3 percent to 8 percent between May 1907 and June 1908, during the Panic.