The survey breaks the stress data down by age, showing how each generation reports feeling regular financial anxiety at different intensities.The biggest source of that stress traces back to one place: high-interest credit card debt. Average credit card APRs are 21%, so a $6,000 balance can easily cost more than $1,200 a year in interest alone. That money isn't paying down what you owe -- it's just renting the debt.According to Motley Fool Money research , 54% of Americans feel stressed about their finances ...