Credit card debt is the canary in the coal mine. It is the signal that tells us which way economies are tracking. And those signals are looking bad.

USA Today reports that credit card debt is racking up faster for older Americans, aged 65 and older. And they're spending it on necessities, like medical care.

It's looking bad on the other side of the Atlantic too. As reported here, the International Monetary Fund is warning of massive defaults across Europe, most notably in Britain which has the highest number of credit card borrowers on the continent.

As the Financial Times tells us, the big worry here is the breakdown in the linkage between credit card defaults and unemployment. Traditionally, one has followed the other but now there are other sources of distress, like bankruptcy filings. That explains why in the United States, losses on credit cards were at a record of close to 10.8% in June, well ahead of the nation's 9.5% unemployment rate.

What's unknown here is whether record levels of consumer debt will make this recession even worse than the 1930s. And that's why credit card debt needs to be watched carefully.