If investors no longer believe that system is viable, a one notch downgrade by a credit rating agency will look like a footnote in the coming economic calamity.

如果投资者认为该系统已经靠不住，那么人们就可能会把哪怕是轻微的评级的下调也当成经济大难将至的佐证。

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Personal credit rating is an important means in improving the efficiency of market transactions. To establish scientific evaluation system is a powerful guarantee in promoting our market economy.

个人资信评估是提高市场交易效率的重要手段，是国家资信评级体系的重要组成部分。

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Think of credit rating as a simple grading system where the top students perform the best on tests (making money) and those at the bottom are the biggest risk for dropping out of school (defaulting).

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But on Wednesday, a donwngrade of US debt by Chinese credit rating agency Dagong Global blamed a shaky and untrustworthy US political system.

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