The 'AA-' rating on Portage, Mich.'s downtown development limited-tax bonds reflects: Strong economic performance, Solid financial operations, and Moderately low debt levels. Mitigating factors include some tax base concentration and limited revenue flexibility. Debt service on the bonds will be paid primarily from tax increment revenues derived from property in the development area. In addition, the city has pledged its limited-tax full faith and credit as security. Portage is halfway between Chicago, Ill. and Detroit, Mich. on Interstate 94 in Kalamazoo County. The 34.5 square-mile city has 44,360 residents. One-third of the land in Portage is zoned for residential. In addition, the city has a large commercial and industrial base. The city's leading employers include Pharmacia Corp. (formerly Uphjohn), Summit
