I found this study to be an interesting one since I am not long off that mark and it's good to know I have something to look forward to.  It also made me a bit curious what the reasoning was behind the results because I was guessing after that age you just don't give a rat's butt anymore about stuff but it was more than that.

In the study they show how as you age your brain actually changes in how it reacts to stress.  I'd call that wisdom but either way it keep us feeling more at ease in daily life. Add to that more mature folks are more self confident and self assured.  Must be all that trying that has helped give us confidence in what our skill sets really are. Other things they noted in the study is that people in their 60's as a rule are more stable and more satisfied with what they have.  See the more of the story here and don't worry, be happy.