Stock prices for UnitedHealth Group and Centene fell by 5% following reports that the payers are experiencing a mismatch between Medicaid enrollees’ care utilization and the rates that states pay.

• UHG CEO Andrew Witty said that the company was seeing “some disturbance” in its Medicaid business at a conference held by Bernstein. Separately, Centene reported in a recent SEC filing that it was seeing “higher than expected claims receipts” between January and April.

• Medicaid accounts for just 13% of UHG’s insurance segment revenues. In contrast, Medicaid represents 60% of Centene’s insurance revenues.