신용카드의 적정한도와 가계의 채무불이행에 관한 연구

In general, credit card companies control card holders’ default by managing their credit limits. It is advantageous for card companies to impose smaller limits to reduce the amount of potential default; however, it may also reduce profits of card companies resulted from downsized card using amount. Besides, the increase of credit limits would provide liquidity to card holders who are in financial distress, serving as a positive platform later for card users to overcome default problem with their improved cash flow. Hence it would be critical for card companies to figure out fair credit limits for each user and impose proper limits coincident with card users’ attribute after considering both positive and negative effects of adjusting credit limits. Here, the fair credit limit refers to the one that is in line with the risk attribute of a card user. This study classified card users based on their credit rating and estimated excess limits (deficient limits) after evaluating fair credit limits of each account at a each time. Furthermore, the impact of excess limit on the delinquency patterns was also analyzed in this study. The specific procedure of analysis is as follows: ① After card users were classified into groups based on their risk attribute, the average limits of each group were calculated, and the results were regarded as fair credit limits. ② Excessive limits (deficient limits) were calculated after subtracting average limits from actual limits of each group. ③ Pure excess limits (pure deficient limits) were calculated after the effect of other factors that might influence the excessive limits (deficient limits) calculated in ② was controlled. ④ The impact of pure excessive limits (pure deficient limits) on default was analyzed. Here are the results of the analysis. First, let’s take a look at the impact of each group’s excess limits on delinquency. Overall, pure excessive limits had a negative relation with delinquency, so pure excessive limits contributed to reducing delinquency, influencing positively. The pure excess limits in total limits reduced delinquency in groups with relatively good credit ratings and the pure excessive limits in financial service limits decreased delinquency in groups with bad credit ratings. The relation between excess limits and frequency of delinquency is as follows. As predicted, excess limits had a negative correlation with the frequency of delinquency. In other words, as accounts got more excessive limits on average during the survival length, the accounts underwent less delinquency. The survival length had a positive correlation with excessive limits in all groups. A notable point is that excessive limits in financial service of the grade1 had a negative correlation with the survival length. It is hard to interpret this relation because the grade1 is the one with excellent credit rating. The fact that the best credit group experienced delinquency even with excessive limits could be interpreted as some uncontrollable adverse events happened to the card users. It might be difficult to prolong the survival length by just increasing credit limits to a certain degree. Next, let’s take a look at the impact of excess limits on the delinquent amount in each group. The delinquent amount is important in that it influences the profit and loss of card companies directly. One of the reasons that caused the credit card crisis in 2003 was the excess credit limits given to users, so positive coefficient, in general, was expected. However, it turned out that excluding the grade 4 and 5, the excess limits had a negative relation with the delinquent amount. In particular, the grade 6 that took up most of the delinquent amount with bad credit ratings had a negative relation and the coefficient was the lowest, which is quite notable. Therefore, it is needed for credit card companies to increase the credit limits to a certain level for users with grade6 in an effort to reduce the delinquency amount. Meanwhile, this study also analyzed panel data analysis(fixed effect model) in addition to using pooled OLS method in an attempt to substantiate the result of research further. Also, an analysis using the 2SLS model was added to control endogeneity with pure excess line ratio of previous month as an instrumental variable. As a result, the coefficient varied slightly, but the same signs and significance consistent to those in the pooled OLS came out. Thus, the result of this study is judged to be reliable. Recently, the surge of household debt has led households in marginal state to need more funds, which is also influenced by the rise of loan rates and decrease of expected income stemmed from deepened economic slowdown. According to the result of this study, positive effect of excess limits, which is providing more buffer to financially distressed households to overcome default based on provided liquidity, is bigger than negative effects, which is increasing the default amount. Yet, it should be noted that providing liquidity to users with long-term financial difficulty will make the potential default amount bigger. This study is judged to be timely and proper in that it analyzed the relation between the credit limit and default in household finance, which hasn’t been studied in depth so far.