García（2007）指出信用卡市場缺乏管制與家庭總債務增加之關聯，起因於近年美國家庭以低利率車貸或房貸償還卡債之故，García（2007）將此稱為信用卡造成之債務掠奪資產現象（coping with debt by plundering assets）。可是過去文獻只著重信用額度對卡債的單向效果，並未探討信用額度與家計總債務間的雙向關聯性。本文以2007年美國Survey of Consumer Finance資料，採用聯立估計模型，印證信用額度與家庭總負債存有正向交互影響。若對消費者信用額度制定上限，可達到抑制卡債以外之家計總負債的效果，本文也模擬對各社經背景消費者可達到抑制負債之成效。此外實證發現信用卡利率對於負債有正向影響，可見債務調整動機使得調高信用卡利率無法作為抑制舉債之有效工具，唯有調降信用卡借款利率與管制信用額度上限兩者同時並行，才可收到抑制負債的效果。

According to Life cycle hypothesis, the amount of credit limit applied by consumers depend on the demand for debt. García (2007), however, finds out that the abuse of credit cards induce consumer's total debt. Our paper establishes the inter-causality between credit limit and consumer's total debt theoretically and have proven it by simultaneous regression model. Our estimations stimulate the effect of restricting the roof of credit limit on reducing consumer's total debt. We find out the effects of reducing credit limit elaborately depend on consumer's education, family income and net wealth. And we further find out raising the interest rate can’t reducing consumer's total debt.