context: Many of the jobs in the city center around state government, headquartered in Springfield. As of 2002, the State of Illinois is both the city and countys largest employer, employing 17,000 people across Sangamon County. As of February 2007, government jobs, including local, state and county, account for about 30,000 of the citys non-agricultural jobs. Trade, transportation and utilities, and the health care industries each provide between 17,000 and 18,000 jobs to the city. The largest private sector employer in 2002 was Memorial Health System. 3,400 people worked for that company. According to estimates from the "Living Wage Calculator", maintained by Pennsylvania State University, the living wage for the city of Springfield is $7.89 per hour for one adult, approximately $15,780 working 2,000 hours per year. For a family of four, costs are increased and the living wage is $17.78 per hour within the city. According to the United States Department of Labors Bureau of Labor Statistics (BLS), the Civilian Labor force dropped from 116,500 in September 2006 to 113,400 in February 2007. In addition, the unemployment rate rose during the same time period from 3.8% to 5.1%.
question: How many workers did the labor force drop by between 2006 and 2007?
answer: 3100