Each board shall establish and implement graduated reimbursement rates for child-care providers participating in the commission’s subsidized child-care program that align the commission’s age groupings with the child-to-caregiver ratios and group sizes adopted by the Health and Human Services Commission. The graduated rates shall provide the highest reimbursement rate to child-care providers that provide care to children in the age group with the lowest child-to-caregiver ratio. The commission shall supply any demographic data needed by the board to establish the rates.