Egan-Jones credit ratings agency says it has downgraded Germany by one notch from AA- to A+ and has issued a negative watch for the country's sovereign debt amid Europe's lingering debt crisis. The U.S. company cited Germany's implicit debt stemming from different mechanisms stabilizing the 17-nation eurozone as the main reason for its decision. Moody's, Standard & Poor's and Fitch - give Germany their best rating and have not questioned the AAA for Europe's biggest economy. Most investors consider Germany's sovereign debt to be a safe haven, significantly driving down the yields and making it cheap for Germany to borrow new funds. Recently a short-term debt auction even brought negative yields, meaning investors paid Germany to take their money.