Most Americans are card-carrying members of a club in which the card is actually the problem. At the end of 2015, the Federal Reserve released data on American credit card debt (this is called “revolving” debt, because you don’t need to reapply for the loan), and the total came to $935.6 billion. As Bloomberg Business notes, this is number has grown $100 billion since 2011, but it’s still less than the $1.02 trillion Americans owed in 2008 before the financial crisis occurred. On average, an American between the ages of 18 and 65 has $4,717 of credit card debt. According to CreditCards.com, the average credit card’s interest rate is 15%. At the minimum payment of $189, it’ll take 10 years and a month to pay off that $4,717. The total payments would amount to $22,869. That’s a $18,155 cost for a very small loan. American credit card borrowing may not be at its peak, but it’s still extremely high, and even more concerning is that the numbers don’t seem to change very much over time. When the economy is hurting, borrowing is high. When the economy is booming, borrowing is also high. And no matter the situation, Americans seem to have credit card debt. The Boston Fed recently released a study examining American credit card debt, and shed some light onto American credit card borrowing and why it’s so pervasive. The biggest reason for such high debt, the study found, was high availability of credit. When someone is offering you credit, it’s hard to say no. “Available credit appears to be the driving factor of debt in both the short and long term,” the study says. Only 35% of credit card users don’t carry a balance–they pay off their bill every month, like you’re supposed to. They use credit cards for convenience, and perhaps to generate bonus points and rewards, not because they need to borrow. If you’re a member of this group, you’re known as a “convenience user.” (Go ahead and pat yourself on the back for not being on the hook for high interest rates, but don’t gloat.) The other, more typical credit card users are known as “revolvers” because they don’t pay off their bills in full so the debt revolves. To them, credit limit increases are essentially invitations to spend more. It’s unsettling: “for revolvers, a 10% increase in credit is followed by a 1.3 percent increase in debt within one quarter and a 9.99% increase in debt over the long term,” the study found. Part of this credit card addiction can be attributed to how easy is to rack up multiple credit cards, and each comes with the opportunity to build up more debt. Many cards offer free teaser years that come with as much as $600 worth of miles or hundreds of dollars in cash back as incentives to apply and to spend. This addiction typically starts in one’s 20s, when people aren’t necessarily earning very much. The availability of funds through credit essentially amounts to extra wealth, and the Fed says this reduces the need to save. Or, in other words, it allows people to spend more. Though it makes sense to borrow against the prospect of a larger salary when a person has an entry-level job, these bad habits die hard and can affect one’s personal finances in middle age and even old age. If anyone needs any incentive to pay down debt, the Fed sums it up with a line that bears repeating often: “Paying off credit card debt has a riskless return that averages 14 percent, which no other asset class can match.” Essentially, there is no better investment a person with credit card debt can make than to pay off that bill.