NY -- Standard&Poor's CreditWire 3/23/98 -- Standard&Poor's today assigned its double-'A'-minus rating to Sioux City, Iowa's G.O. refunding bonds due June 1, 1999-2002. At the same time, Standard&Poor's affirmed its double-'A'-minus rating on the city's outstanding G.O. bonds. The rating reflects: -- A regional economy with strong links to the agricultural sector, -- Sound financial position, and -- Moderate debt. Sioux City is a regional economic center for west-central Iowa and portions of South Dakota and Nebraska. The agricultural sector is centered predominantly in meat processing, with IBP Inc. (headquarters and processing - 4,500) and Morrell Inc. (1,350) listed as leading employers. Manufacturing and services also contribute to the economy with Gateway 2000 (headquarters