3.__School administrative unit; contribution.__For each school administrative unit, the commissioner shall annually determine the school administrative unit's contribution in accordance with the following.

A.__The school administrative unit's contribution to the total cost of education is the lesser of:

(1)__The total cost for each municipality as described in subsection 1 or 2; and

(2)__The total of the full-value education mill rate calculated in section 15671-A, subsection 2 multiplied by the certified state valuation for the year prior to the most recently certified state valuation for each municipality in the school administrative unit.

B.__The state contribution to the school administrative unit's total cost of education is the total cost of education calculated pursuant to subsection 1 less the school administrative unit's contribution calculated pursuant to paragraph A.

4.__Method of cost sharing; exception.__For the purpose of local cost sharing, the provisions of subsection 3 do not apply to municipalities that are members of a school administrative district or a community school district whose cost sharing formula was established pursuant to private and special law prior to January 1, 2004.__For each municipality that is a member of a school administrative district or a community school district whose cost sharing formula was established pursuant to private and special law prior to January 1, 2004, the cost sharing formula established pursuant to private and special law determines each municipality's local cost of education.

5.__Effective date.__This section takes effect July 1, 2005.

§15689.__Adjustments to state share of total allocation

Beginning July 1, 2005, adjustments to the state share of the total allocation must be made as set out in this section.