Diversity of geography, fuel, and economies, Regulatory support, Plant operating efficiency, and Continuing cost reduction program. Parent company debt increases debt service burden of the utilities, and Purchased power obligations add roughly $800 million debt equivalent to balance sheet. The rating on Public Service Co. of Colorado (PSCo) is based on the consolidated credit profile of utility holding company Xcel Energy Inc. and its vertically integrated utility subsidiaries, PSCo, Northern States Power Co. (NSP-Minnesota), Northern States Power Wisconsin (NSP-Wisconsin), and Southwestern Public Service Co. (SPS). Minneapolis, Minn.-based Xcel had $7.4 billion of debt and $105 million of preferred stock outstanding as of March 31, 2007, of which PSCo had $2.2 billion of debt outstanding. The rating on Xcel reflects its
