Sec. 9. (a) Obligations entered into before January 1, 2009, for the acquisition, expansion, remodeling, and improvement of an athletic and exhibition coliseum shall be retired by using money collected from a tax imposed under this chapter.
(b) With respect to obligations for which a pledge has been made under this section before January 1, 2009, the general assembly covenants with the holders of these obligations that:
(1) this chapter will not be repealed or amended in any manner that will adversely affect the imposition or collection of the tax imposed under this chapter; and
(2) this chapter will not be amended in any manner that will change the purpose for which revenues from the tax imposed under this chapter may be used;
as long as the payment of any of those obligations is outstanding.