Standard&Poor's Ratings Services has assigned its 'AA-' rating to Sioux City, Iowa's GO urban renewal bonds series 2003A and 2003B. At the same time, Standard&Poor's has affirmed its 'AA-' rating and 'AA-' underlying rating (SPUR) on the outstanding debt. The ratings reflect the city's: Regional economy, with strong links to the agricultural sector; Moderate wealth levels; Sound financial position; and Moderate debt burden. Credit factors precluding a higher rating at this time include: The city's high debt-service carrying charges; Moderate taxpayer concentration; and Reliance on sales tax revenues to pay debt service, which are inherently subject to economic volatility. Sioux City is a regional trade, service, and health care center for west-central Iowa and portions of