Credit Card Debt The average credit card debt for a recent year was $9205. Five years earlier the average credit card debt was $6618. Assume sample sizes of 35 were used and the population standard deviations of both samples were $1928. Is there enough evidence to believe that the average credit card debt has increased? Use a = 0.05. Give a possible reason as to why or why not the debt was increased. Source: CardWeb.com