Standard&Poor's Ratings Services assigned its 'AAA' long-term rating to Plano, Texas' series 2013 general obligation (GO) refunding and improvement bonds. At the same time, we affirmed our 'AAA' rating on the city's existing GO debt. The outlook is stable. In our view, the 'AAA' rating reflects the city's: Deep, diversified economic and employment base, and participation in the strong Dallas-Fort Worth economy; Very strong wealth and incomes; Conservative and sophisticated financial management policies that include long-range budget and capital plans; Historically strong financial position, coupled with very strong reserves; and Rapid amortization of principal, along with moderate additional capital needs. An ad valorem tax levied against all taxable property in the city secure the bonds. Officials will refund