Credit card debt is rivalling mortgages as top debt source

American consumers are holding an average $29,800 in non-mortgage debt and are spending worrying shares of their monthly income to service it.

A study from Northwestern Mutual has found that on average, 34% of people's monthly income goes toward paying off debt, while the same share doesn’t know how much of their income goes on debt payments and 20% are not sure how much debt they have.

Although the survey discovered that average debt was down almost $10K from a year ago, the impact of what they owe is causing consumers to feel anxious (45%), guilty (35%), or physically ill (20%).

The leading sources of debt for most Americans is a tie between mortgages and credit cards, according to the study. An equal 22% of U.S. adults listed each as their main source of debt, more than double the next two highest sources — car loans (9%) and personal education loans (8%).

"The road to financial security is long, even in the best of circumstances," says Emily Holbrook, senior director of planning at Northwestern Mutual. "By carrying high levels of personal debt that road gets even longer, often requiring all kinds of detours and other twists and turns. The fact that there's been some year-over-year improvement in debt levels is good, but the numbers still remain worryingly high."

Nearly one-third of Americans (31%) are paying interest rates on their credit cards greater than 15%, 12% are only making the minimum payment each month, and 19% are unsure of the interest rate.