When do we reach our financial decision making peak?

Financial sophistication peaks in our early 50's. Younger adults and older adults borrow at higher interest rates and pay more fees than middle-aged adults.

These conclusions come from a fascinating paper I read recently.

The authors hypothesized that financial sophistication would depend on a combination of analytic ability and experiential knowledge.

Their research on cognitive aging implied that analytic ability follows a declining concave trajectory after age 20. Our brains function as well as they will in our early 20's, then degrade from there.

The authors also hypothesized that experiential knowledge follows an increasing concave trajectory due to diminishing returns. The older we get, the more experience we have. The more experience we have, the better decisions we can make. But, each unit of experience does not provide the same benefit as the unit before. Hence the diminishing returns. Our experience helps us make better decisions, but each bit of experience benefits us less and less over time.

When adding together the effect of cognitive decline and experience with diminishing returns, we end up reaching our peak at some point and then our abilities decline over time.

The same thing can be seen in other pursuits. Baseball players peak in their late 20's. Mathematicians, theoretical physicists and lyric poets peak around age 30. Chess players peak in their mid 30's. Autocratic rulers peak in their early 40's. Authors peak around 50.

The authors validated their hypothesis by showing that younger and older financial decision makers pay too much in interest and fees. Sure enough, those in their early 50's pay the least in interest in fees, seemingly validating the cognitive decline/experience with diminishing returns thesis.

Here's an interesting question: what age person should you want to work with to help you make financial and investing decisions? Would you want to chose someone in their mid 50's, whose cognitive abilities are declining and whose experience doesn't make up for this decline? I don't think so.

You'd probably want someone on the upswing, someone whose cognitive abilities may be declining, but who has enough experience to make up for that decline. Perhaps you'd want to pick someone who would reach their sweet spot of optimal decision making in the future, who still had the best benefits of aging and experience ahead of them.

Okay, this is a shameless, self-promoting plug. I'm in my late 30's and will become a better investor over the next 15 years. Doesn't that sound like the right target, instead of someone with so much experience they're in decline? If you're going to work with someone for 30 years to reach your goals, wouldn't you prefer someone on the upswing instead of the downswing. I sure would.

Nothing in this blog should be considered investment, financial, tax, or legal advice. The opinions, estimates and projections contained herein are subject to change without notice. Information throughout this blog has been obtained from sources believed to be accurate and reliable, but such accuracy cannot be guaranteed.