Medicaid supplemental payments are going up, but it's difficult to know by how much because states don't always keep accurate data, according to a study by the Government Accountability Office.
Supplemental payments reached an estimated $32 billion in 2010, according to the report. They are payments by states to hospitals and other providers to help offset Medicaid costs and pay for the uninsured.
But states' reporting of the payments is sometimes incomplete, making an accurate total difficult, the GAO said.