N.Y. Comp. Codes R. & Regs. tit. 10, § 86-1.16 – Statewide base price.

(a) For periods on and after December 1, 2009, a statewide base price per discharge shall be established based on targeted statewide Medicaid inpatient hospital expenditures and case-mix and wage neutral reimbursable Medicaid acute operating costs derived from the base period identified in subdivision (b) of this section, and as adjusted for inflation between the base period and the rate period in accordance with trend factors determined pursuant to applicable provisions of section 2807-c(10) of the Public Health Law, but excluding costs related to graduate medical education, exempt units, patient transfers, high-cost outliers, alternate level of care, and non-comparables. Such trended operating costs shall then be divided by Medicaid inpatient discharges in the base period identified in subdivision (b) of this section to establish the average statewide base price per discharge for the applicable rate period.
(b) For periods on and after December 1, 2009, the "base period" shall be the 2005 calendar year and "operating costs" shall be those reported by each facility to the department prior to July 1, 2009.
1. (1) For those hospitals operated by the New York City Health and Hospitals Corporation, the base period shall be for the period which ended June 30, 2005, and for those hospitals operated by New York State, excluding the hospitals operated by the State University of New York, the base period shall be the 12-month period which ended March 31, 2006.
2. (2) Discharges, as defined in section 86-1.15(n) of this Subpart, used for direct graduate medical education adjustments shall be based on reported 2007 data.
3. (3) Discharges, as defined in section 86-1.15(n) of this Subpart, but excluding the factors set forth in section 86-1.15(n)(3) of this Subpart, as used for non-comparable adjustments shall be based on reported 2007 data.
  (c)
4. (1) For the period effective July 1, 2011 through March 31, 2012, the statewide base price shall be adjusted such that total Medicaid payments are decreased by $24,200,000.
5. (2) For the period May 1, 2012 through March 31, 2013 and for State fiscal year periods on and after April 1, 2013, the statewide base price shall be adjusted such that total Medicaid payments are decreased for such period and for each such State fiscal year period by $19,200,000.