It's no surprised that these groups report the most stress. I'm a Gen X'er and many of us have mortgages to pay, children to raise, careers to juggle, car loans and credit cards to pay, and try to take a vacation or two.
Those who are younger have student loans and not-so-great job prospects.
It's a lot of stress to have! There's a lot to think about!
Millennials and Gen Xers feel the most stress about money
http://fortune.com/2015/02/04/millennials-and-gen-xers-feel-the-most-stress-about-money/