2012 has started off with a mixed bag of results for many credit card issuers, as some banks and lenders are seeing their delinquency and default rates drop, while others are noting an increase.

Delinquencies, or late payments, are tracked when customers' payments are late by 30 or more days. If a cardholder is late on a payment, the card issuer will typically assess him a late payment fee. Card issuers track late payments because it's an indicator of whether or not an account may go into default.

Defaults occur when customers habitually don't make the required minimum payment on their account. When a customer defaults, the bank has decided that it's not going to be able to collect any money on the outstanding balance, so it writes off the account. According to the Associated Press, card companies usually wait until a balance is six months past due before writing it off. When delinquencies and defaults are low, it's good for both the bank and the cardholder.

While delinquencies incur late payment fees, cardholders who go into default may find that they're unable to get credit cards, and if they can, the interest rate on them is usually very high, since card issuers will deem them a risk.

This week, many card issuers announced that their rate of late payments had declined in December, a sign that cardholders have been keeping up with their payments. Discover rate inched down from 2.43 percent in November to 2.32 percent in December. December's decline is over a percentage lower than last year's rate, which was 3.91 percent. Capital One's delinquency rate dropped from 3.73 percent in November to 3.66 in December. Last year, Capital One's delinquency rate was 4.09 percent. JP Morgan Chase & Co. had a December delinquency rate of 2.48 percent, down from November's 2.55 percent and last year's 3.47 percent.

American Express has some of the lowest delinquency rates in the business because compared with some of the other issuers, it has more affluent customers and stricter rules for its cardholders. Amex received late payments on 1.4 percent of balances in December, down from 1.5 percent the previous month and 2.1 percent the previous year.

In terms of defaults, card issuers had varied results for December. Discover's defaults rose to 3.15 percent of balances from 3.04 percent in November, with the issuer writing off $46.4 million on an annualized basis. However, last year its charge-off rate was 5.94 percent of balances. Chase also experienced a higher default rate in December, as it wrote off 4.11 percent of balances on an annualized basis, compared with the previous month's 4.02 percent. However, Chase's charge-off rate improved from the previous year, when it wrote off 6.99 percent of balances.

Other players managed to improve their default rate for both the month and the year. Capital One's December default rate was 3.98 percent, or $185 million of balances on an annualized basis. This is down from 4.29 percent the previous month and 7.01 percent the previous year. American Express wrote off $53.7 million on an annualized basis for December, which represents 2.3 percent of balances. This is down slightly from November's 2.4 percent, but it's nearly half of its default rate from last year, which was 4.1 percent.

The S&P/Experian Consumer Credit Default Indices, which look at consumer credit default rates on first and second mortgages, bank cards and auto loans, noted that national default rates are also falling. On a composite measure, the picture for December compared to a year ago has improved from an index level of 3.01 percent in December 2010 to 2.24 percent in December 2011. For bank cards alone, the index fell from 6.73 percent in December 2010 to 4.60 percent in December 2011.

While first mortgage defaults on this index have been creeping upward since August, David M. Blitzer, managing director and chairman of the Index Committee for S&P Indices says in a press release, "Bank card default rates, on the other hand, were favorable, falling to 4.6 percent in December. This is more than a full percentage point below the 5.64 percent we saw as recently as July 2011."