Median and Average Meanings

There’s a story about Bill Gates’s wealth and height you’ve probably heard. If not, let’s quickly share it here. If Gates were to walk into a room of you and twenty-five friends, the difference in average height and median height would be small.

However, the difference in average income and median income would be large. Gates’s wealth raises the mean because it’s relatively ginormous. Even in a room of millionaires, Gate’s presence changes the average from one-million to four-billion. That’s a lot.

This story is helpful to keep in mind because averages hide nuances.

In 2016, the average student loan debt was $37,000. However, the median figure was $17,000 and one-fourth of all borrowers owed less than $7,000. Part-of-the-reason the average is so far from the median is because of graduate school, one-in-four post-graduation debt-holders had more than one-hundred thousand dollars in debt. My wife attended medical school, and I can attest to the amount.

This median approach might paint a rosier picture.

Retirement accounts show the same point, only in the opposite direction. The average balances is $100K whereas the median is $24K.

“Often an average is such an oversimplification that it is worse than useless.”

How to Lie

Average can become an If/Then word. If the average is presented, then we can attempt to find the median as well. Bill Gates will be our patron saint here. Imagine him, staning with a Diet Coke in hand, reminding you to find the median too.

Another fun part of you and twenty-five friends is “the birthday bet”.


Made up Start up: FinLit Deposit

Photo by Pixabay on

No one is happy with financial literacy. Maybe it’s the questions researchers ask, maybe it’s a generational thing, maybe it’s soft skills. It’s probably a lot of things.

Part-of-the-reason we don’t have a great idea is because we don’t have a great way to test it. A lot of FinLit research follows these steps:

  1. A natural experiment occurs. Sometimes it’s in time. One cohort has no mandate, another has the mandate. Alternatively it could be a law in one state, but not a neighbor.
  2. Students get some combination of classes, videos, etc. To me the treatment seems weak, but you be the judge.
  3. Students answer questions about what they learned.

This structure suffers because it measures what’s easy rather than what’s meaningful. What if we reversed this? What if instead of prioritizing measurement, we prioritizied meaningfulness?

For our start up FinLit Deposit, we’d give every student $100 the first week. If they have at least $100 in the account each subsequent week, they get $25 more. If the account dips below that amount, no deposit. If it recovers, the deposits begin again.

This systems offers students real choices with real money. Save or spend. Invest or rest. Investors often note that paper trading is not the same emotional ballpark as real money. That should apply here too.

We could partially fund this with a grant that studies decision making. What if some kids got physical bills–good day Mr. Franklin- and others direct deposit. Dollars to doughnuts, I’d wager that the mentally accounting will differ.

If grants aren’t available to kickstart this start-up, let’s get some public money. Athletic scholarship total almost $3B. Academic and need scholarships are in the tens of billions. There’s already (!!) $630M spent on financial education. That’s already $200 for each senior. What’s wild is we already do these these kinds of things.

Young people tend to not be great decision makers. So what. No one is fully optimal. If our hypothetical students spend their semester of savings on a concert is that much different than their parents tax-refund choices?

The only problem I see in this is how FinLit Deposit actually makes money. Maybe some financial literacy program actually teaches that.

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Update 2/6/2020


Maximizing a 401K

There’s an interesting investing idea in personal finance to be like Rip van Winkle. If investors don’t earn the market returns because they churn, maybe they would be better off setting it and forgetting it, of sleeping-on their investments.

I was reminded of this story because I forgot a password. Does invest like you forgot your password have the same flair? Eventually I logged in and checked our contribution amounts for 2020.

While poking around I wondered what a retirement account would look like if someone were to maximize their 401k ($19,500 in 2020) each year. Sometimes the government changes the limit of what an employee and employer can contribute to a retirement account. As someone who likes simple and effective plans I thought this was great financial advice. I could see advisors telling their clients, just aim to hit the max number each year and you’ll have this much.

I calculated the rate changes each year and found out that contribution limits change at about the same rate of inflation. Of course. The IRS calls these ‘cost of living adjustments’. Sometimes you just need to stumble on things yourself.

The S&P average over the last thirty years was 9.69%. The picture looked like this.

This doesn’t account for an employer match, social security, or other savings but it’s comforting to know that the real 4% withdraw at retirement is $93,000 annually.

Digging into this made me realize how much variation can occur in planning. Cost-of-living, family situations, businesses, multi-income families, income levels, mortgages, taxes, and so on can all swing the equation one way or another. Ditto for flexibility in needs and wants.

However, just because there is a lot to consider doesn’t mean there’s not a simple plan. Specific predictions are futile but ballpark approximations are possible, helpful, and a good way to frame potential outcomes.