To discourage moral hazard the interest rate should be at a penalty rate and, reflecting the rising risk, increase with the amount borrowed.

为了阻止道德风险，其利率应当是惩罚性的，而且随着借债数额的上升而提高，以体现风险的上升。

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Where there is any interest that cannot be paid on time, compound interest shall be calculated at a penalty interest rate.

对不能按时支付的利息，按罚息利率计收复利。

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Bank of America has not had a penalty interest rate on its credit cards since the industry was overhauled by Congressional legislation in 2009.

FORBES: This Week in Credit Card News: Amex Profits, Debit Fees, Secured Cards

Unlike a wholesale interest rate increase, borrowers would be charged the penalty rate only on new purchases after the rate is changed, and a customer will receive 45 days advance notice of any penalty rate being placed on their account.

FORBES: This Week in Credit Card News: Amex Profits, Debit Fees, Secured Cards