The 'AA-' rating on Sioux City, Iowa's GO bonds reflects the city's: Regional economy with strong links to the agricultural sector, Average income levels, Sound financial position, and Moderate debt burden. Offsetting credit factors include the city's: High debt service carrying charges; and Sales tax revenues to pay debt service, which are subject to economic volatility. Sioux City is a regional trade, service, and health care center for west-central Iowa and portions of South Dakota and Nebraska. The city serves a population of 85,000, which has shown relatively slow growth during the 1990s (increasing 5.6%). The city has stepped up efforts to stimulate redevelopment in the central business district and new development along targeted corridors, through public and private initiatives.