NEW YORK (Standard&Poor's CreditWire) Nov. 4, 1999--Standard&Poor's today assigned its single-'A' rating to United HealthCare Corp. d/b/a UnitedHealth Group's $150 million two-year senior unsecured floating rate note offered under Rule 144A due Nov. 5, 2001. The proceeds of the offering will be used for general corporate purposes, which may include working capital, share repurchases, repayment of short-term debt, and business acquisitions. The company's debt-to-total capital ratio is about 14% as of Sept. 30, 1999, and projected earnings before interest, depreciation, and amortization, and taxes should provide more than 20 times coverage over interest expense in 1999, which are consistent with its current rating category. The rating reflects the company's strong business position, improved earnings profile, good