The plan is administered by 298 branch offices, and insured 30.7 percent of the population in 1997. Its premium in 1997 was fixed at 8.5 percent of payroll, divided
equally among employers and employees. While society-based plans may offer extra benefits, the
government-managed plan offers only one package. Because its members are generally lower-wage
earners than those in society-managed plans, the state contributed 13 percent of benefit costs and all
administrative costs. Mutual aid associations cover public sector employees and insured 9.2 percent of
the population in 1997.