7-12-2176. Interest rate on unpaid assessments. (1) Except as provided in subsection (3), the installments of assessments remaining unpaid bear simple interest at an annual rate equal to the sum of:

(a) 1/2 of 1% a year; plus

(b) the average interest rate payable on the outstanding bonds or warrants of the rural special improvement district at the time the assessment is levied each fiscal year; plus

(c) at the option of the board of county commissioners, up to an additional 1/2 of 1% a year.

(2) The board of county commissioners may subsequently reduce or eliminate the additional interest rate allowed under subsection (1)(c). If the additional interest rate is reduced or eliminated, it may not be subsequently increased or reimposed.

(3) If and so long as the bonds or warrants secured by the assessments bear interest at a variable rate, the installments of assessments remaining unpaid must bear simple interest at an annual rate equal to the sum of:

(a) 1% a year; plus

(b) the interest rate payable on the outstanding bonds or warrants of the rural special improvement district at the time the assessment is levied each fiscal year; plus

(c) to the extent that the interest rate on the bonds or warrants is then less than the maximum rate prescribed for the bonds or warrants or if there is no prescribed maximum rate, up to an additional 1% a year, as may be prescribed by the board of county commissioners in the resolution authorizing the issuance or sale of the bonds or warrants.