The corporate credit rating on Public Service Co. of Colorado (PSCO) is based on the consolidated credit profile of Xcel Energy Inc., parent company of Northern States Power Co. (NSP-Minnesota), Northern States Power Wisconsin (NSP-Wisconsin), Public Service Co. of Colorado (PSCO), and Southwestern Public Service Co. (SPS). The rating reflects the strength of the utilities' business profile ('4' on a scale of '1' to '10', with '10' being the weakest), which incorporates the generally supportive state regulation that governs each utility's rates, the relatively low-cost power supply and overall fuel diversity, and the broad geographic region encompassed by the combined service territories of Xcel Energy's subsidiaries. Xcel has only a small amount of unregulated generation at its Xcel International subsidiary,
