All Employees: Professional and Business Services: Management, Scientific, and Technical Consulting Services in Illinois was 99.49378 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, All Employees: Professional and Business Services: Management, Scientific, and Technical Consulting Services in Illinois reached a record high of 101.94352 in January of 2023 and a record low of 24.86929 in January of 1990. Trading Economics provides the current actual value, an historical data chart and related indicators for All Employees: Professional and Business Services: Management, Scientific, and Technical Consulting Services in Illinois - last updated from the United States Federal Reserve on March of 2024.