". . . the city could reduce that tax extension by several years if it more aggressively paid off the principal and interest on rail’s construction bonding."  Or how about holding off on using G.O. bonds, which are about 3% and using the commercial paper (about 1%) first?  According to a recent cash flow projection, HART anticipates issuing $590 million in debt this fiscal year -- $350 million in bonds in Sept. and the rest in commercial paper next Feb. - May.