Complex sentence: Established in 1993, the HZZO is the country's national social health insurance fund and its primary source of health financing, and after 2002, citizens were no longer allowed to opt out of the public insurance system.
Split into simpler sentences: Established in 1993, the HZZO is the country's national social health insurance fund and its primary source of health financing. After 2002, citizens were no longer allowed to opt out of the public insurance system.