 A 2002 survey by the state of Georgia's subsidized healthcare system, PeachCare, found that Walmart was the largest private employer of parents of children enrolled in its program; one quarter of the employees of Georgia Walmarts qualified to enroll their children in the federal subsidized healthcare system Medicaid.A 2004 study at the University of California, Berkeley charges that Walmart's low wages and benefits are insufficient, and although decreasing the burden on the social safety net to some extent, California taxpayers still pay $86 million a year to Walmart employees.On September 4, 2008, the Mexican Supreme Court of Justice ruled that Walmart de Mexico, the Mexican subsidiary of Walmart, must cease paying its employees in part with vouchers redeemable only at Walmart stores.