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VOGUE RAN AN ARTICLE a decade ago about Marissa Mayer, then Yahoo’s CEO. The opening quote from Mayer grabbed my attention: “I really like even numbers, and I like heavily divisible numbers. Twelve is my lucky number—I just love how divisible it is. I don’t like odd numbers, and I really don’t like primes. When I turned 37, I put on a strong face, but I was not looking forward to 37.”
Mayer’s statement resonated with me. I’ve been afflicted with a similar lifelong obsession with numbers. When I was very young, my dad wrote math problems on yellow lined paper for me to solve. My sister Lynn taught me elementary geometry when I was in third grade. I had a fascination with baseball statistics and memorized all kinds of numbers from my baseball cards. As I got older, I became fixated on grade point averages and Scholastic Aptitude Test scores.
I’ve never been diagnosed with obsessive-compulsive disorder (OCD). I have no particular fear of germs, and I don’t engage in handwashing rituals or similar activities. Still, there are components of my personality that seem to place me on the OCD spectrum.
If I see a cat video I like, I can watch it dozens of times and still find it funny. I have certain silly phrases and movie quotes that I never seem to tire of repeating. (I can picture members of my family nodding their heads as I write this.) And, yes, sometimes I get preoccupied with numbers.
Like Mayer, I prefer even numbers, though odd numbers that end with five are acceptable. Also like Mayer, I think 12 is a great number and I’m not fond of prime numbers. I was a bit annoyed with myself that, in 2023, I had 23 HumbleDollar articles published and 23, of course, is a prime number. With a little foresight, I could have made it 24, which—as a multiple of 12—is very desirable. I console myself that writing 23 articles in 2023 has a certain cachet. Maybe I should shoot for 24 in 2024 to keep the pattern going.
My numerical quirks have affected how I approach my finances. I’m sure some of these considerations may seem silly to those unafflicted by a numbers fixation. Still, I receive emotional benefit from these mostly benign practices. Here are some of the ways my OCD tendencies have trickled into my financial life:
Even number of funds. In any given portfolio, I prefer to hold an even number of funds. For example, my 401(k) has eight funds. At one time, it had six. It has had as many as 10. It’s never had nine. Once, it briefly had seven, but that made me uncomfortable.
Preferred bond denominations. When I buy a new savings bond or certificate of deposit, I only purchase certain face values. For example, $10,000 and $12,000 are acceptable. What about $11,000? Never.
Spreadsheets. I’m obsessed with spreadsheets. I probably said all I need to say about this topic in an earlier article.
Symmetrical rebalancing. At various times, I’ve rebalanced my portfolio to have roughly equal amounts in multiple funds. I could then easily monitor the “horse race” and see which funds were winning.
Closure. I don’t really want my mind to be filled with financial numbers and deliberations. I prefer closure—the sense that I don’t have to think much about my finances any more. My decision to forgo rebalancing is, in part, due to this. I want my finances on autopilot so I can devote fewer brain cells to thinking about investments.
Retirement has been helpful in this regard. Before, I felt driven to monitor my financial progress. Now that I’ve retired, the accumulation phase is largely over. It’s much easier to avoid checking portfolio balances and to stop financial numbers from invading my brain uninvited.
Control. Having a touch of OCD makes me want to feel in control of my finances. I don’t currently use a financial advisor. If I did, I think I’d always be looking over the advisor’s shoulder. I agree with David Gartland’s statement in a recent article: “I feel better finding out I made a mistake with my money, rather than learning someone else made a mistake for me.”
I’m not suggesting that readers follow in my footsteps. I don’t think the practices above have materially affected my finances. Perhaps a few opportunities were missed. On the other hand, if any of you see something of yourself in me or Marissa Mayer, take comfort: You aren’t alone.
Ken Cutler lives in Lancaster, Pennsylvania, and has worked as an electrical engineer in the nuclear power industry for more than 38 years. There, he has become an informal financial advisor for many of his coworkers. Ken is involved in his church, enjoys traveling and hiking with his wife Lisa, is a shortwave radio hobbyist, and has a soft spot for cats and dogs. Follow Ken on X @Nuke_Ken and check out his earlier articles.
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Retired math teacher here. I bet you’re glad this didn’t happen to you: Some years ago I tripped over a backpack in the school lobby and slammed my forehead into the door jamb. At the emergency room, the physician said, “You really need 9 stitches, but I always do a prime number, so I’ll do 11.”
Thank goodness the physician was not into Fibonacci numbers!
Good one. Just think: If you had needed 24 stitches, the doc would have given you 5 extra instead of 2.
We like to keep the math easy. By that, I mean easy to look at and rebalance.
Our Roth accounts are 25% S&P500, 25% Extended Market, 25% total international stock, 25% short term bond fund. Rebalancing is a cinch. All the numbers should be close to the same.
IRA’s take a similar approach except stock portion is 10% in each of the above and 70% is broken up into very roughly equal rungs of a cd/treasury/tips bond ladder. We are just entering the withdrawal phase so a portion of each ladder rung is used for that. Again, rebalancing can be done without a calculator. It would be much simpler to use a bond fund rather than a ladder but we like the certainty of maturing bonds.
Taxable accounts is more of a hodgepodge because of rebalancing tax implications. Oh well, symmetry in this area is more of a journey.
Very nice. Your Roth account approach in particular is quite appealing to me.
But every positive integer has primes factors. They are the beautiful atoms of the number line, composable into all others. Please consider reconsidering.
Okay. Possible future article titles: Time for Primes, In My Prime, Embracing My Inner Prime, Primed for Success, Prime Priority, Prime Beef No More.
Irrational but not a return killer and if it helps you sleep at night, all the better.
Math Phobic here. In my two advanced degrees, Statistics and Quantitative Math were a major challenge for me. Only my ability to study very hard and memorize things for short periods enabled me to get A-‘s in those courses…my weakest grades.
I have always admired and been jealous of Math Nerds, but I have been comforted knowing that God gives us all different gifts. His gift to me was earning an income sufficient to be able to hire Math Nerds when needed.
Thanks fr a fun article Ken.
The description of Ken’s family confirms that love or proficiency in math is purely genetic!
Ken, I have a friend who claims to have CDO. It’s similar to OCD except that the letters are in alphabetical order. Seriously, this article is very interesting and I’ve witnessed what you have described in my engineer tax clients.
😀
So he has a Compulsive Disorder Obsession…can’t stop thinking about how compulsive he is. 😄
Rebalancing used to be my weak spot! I used to stress over it, trying to nail every detail down to the second decimal point. I found myself making lots of small trades, especially when I first started managing my own portfolio. Sadly, I made the mistake of rebalancing in taxable accounts early on, which led to unnecessary capital gains taxes. That stung!
Thankfully, I’ve learned to be more disciplined now. I let the portfolio drift to about 1.25 times the target before making any adjustments.
Prime numbers are what make the world go ’round. But then I’m a cryptography geek.
Interesting! I am not into spreadsheets but I can empathize with your interest in numbers. Except that my preference is for odd numbers. Especially 3, 5 and 7, although not 13 or 17. Totally irrational, of course, given that even numbers feel unbalanced to me.
My husband adores prime numbers and is especially enraptured that his birthday is 5/17. He also demands that we celebrate Pi Day (3/14) with either pizza or pie for dessert.
I’m a words person, myself. I avoid math as much as possible!
Kathy, I think the numbers thing is highly individualistic. I have no idea why I have the particular affinities I do.
Do you also look for patterns in dates? For instance, my wife pointed out you got this article published on an odd date, but 3+21=24. So, it evens out. Or, do you note the palindrome dates of the first part of this century? The next is 4/2/24.
No, I don’t really look for patterns in dates, although I did take Jonathan to task for scheduling the article on an odd date. At least it wasn’t a prime. 🙂
Show me an engineer or accountant free of some level of OCD, betcha you can’t! That’s one reason why we are good at what we do!
Word to the wise on rounding your savings bond amounts to preferred numbers: I use distinct numbers for cds and bonds for easier tracking. Yes, 6k, 21k, 44k, etc. The 10k amounts were getting confusing in Quicken. Which one did I post interest for or redeem? Now things are simpler, at least for me.
As I have noted before I (was) am? A computer geek.
I was at a conference years ago where the keynote speaker said all us computer nerds were somewhere on the Asperger’s scale.
Close to the same thing you mention Stacey.
That’s a good trick, Stacey. I haven’t had any issues keeping track but I can see how what you do could be a good practice for some people.
Ken, You are certainly in your “prime” when it comes to writing! But you are not as “odd” as you think, and definately not alone in your number sense. Personally, I can’t bring myself to transfer funds in amounts that are divisible by 9. Our quirks (OCD tendencies) likely allowed greater ease toward sticking to our financial goals.
Jeff, I can always “count” on you to bring a smile to my face. You sure know how to “factor” in the right words in your comments!
Ken thanks for your numerical comments. When people used to balance their “checkbooks” (?) I know there was a huge tendency to round up. My “fun with numbers” takes a different tack. Whenever I fill-up the car with gas I never round-up because I want to have another check that I bought gas without saving receipts. Instead I try to end the fill-up with symmetry or a numerical palindrome. Instead of $23.50 I would try for $23.32. Instead of $31 I would try for $31.13. When I look at my statements I have more confidence that I bought the gas.
Ken – I see myself in some of your preferences – – – although I like prime numbers. When I go to the Y for a workout, I often use a prime number combination for my locker combination. I polished my math skills with baseball statistics, and my Dad also pushed my math skills with timed worksheets of addition, subtraction, multiplication, and division. I used to “test” my engineering calculator by taking the square root of a number many times, then square it the same number of times to see how the round-off difference accumulated (I’ve not done that in a long time).
Jeff, welcome to the stable of HumbleDollar writers. The calculator test sounds familiar. My friend and I also played with our digital watches when we were bored during engineering class lectures. The game was to capture the lowest stopwatch time possible. Thanks for reading and commenting.
Great article Ken. I definitely share your affinity for spreadsheets, and have some number quirks myself. In the past when paying off a mortgage, if we were close to a thousands milestone, I might add a little extra to break that principal value. We have a number of nieces and nephews involved in charitable endeavors that we love to support. We decide how much we want to contribute, but I like to watch the amount contributed and make our contribution so we put the total over the goal. Childish – sure. But it made me happy.
I’m going to expand on Dick’s comments below about engineers. In my case, and my experience, engineers like to know how things work. The obsession over numbers and details is a result of that. My usual inclination is to dig in, do the research, figure it out, …. It’s a big part of what led me to HD and starting to write articles.
I’m a few articles from 150 – so I’ve been upping my game – got to hit that milestone!
Rick, thanks for reading and commenting. 150 articles is an amazing milestone. You are one of the prolific pillars of HumbleDollar, along with Adam, Dick and Dennis (not to mention our esteemed editor). Keep putting out the good stuff!
Hey Ken, you’re an engineer, that’s what engineers do, they obsess over details and numbers, they actually like numbers. That’s a good thing as we don’t want stuff falling down or blowing up. I have one son who is a civil engineer, now systems designer, I know what happens.
While I am not sure what a prime number is, I share your view on closure although in my case it’s been a lifelong affliction. I like everything possible on autopilot. Alas, I still check my investments daily, well two, three times daily.
I suppose it is an obsession of sorts, and frankly I don’t know why I do it, I just have a dislike for red numbers I guess.
I’d love to get to a point where I’m checking investments maybe once a month at most. It’s rather tempting to check more often when markets are rising, though.