I can’t stand it when I have a stock/ETF position and it’s not a nice rounded number.
E.g. 2354 of a certain stock (for instance due to stock dividend) drives me nuts. I’ll always drive for nice round numbers 500, 1000, 2500, etc. - not just to make options trading easier (writing covered calls) but also for esthetic reasons.
In the 2354 example… that would trigger me to buy a few more shares to get to 2500.
Do you have any irrational habits that you’re aware of and stick with?
That’s when I place market order for 646 stocks.
Round lots are not irrational.
Now I even own fractions of shares, it drives me nuts
Mental accounting galore! I like to buy shares in tranches that the next dividend attributed to the tranche will buy a round number of shares…
I just look at the consolidated spreadsheet view. E.g. my round number for BTI is 1000 shares.
No need to look behind the curtain where 738 shares are in Swissquote’s custody and 262 shares are in IBKR’s custody …
(I also don’t write covered calls which makes using this one weird trick™ a little easier)
Obligatory math geek commentary: you anyway can’t hold an irrational number – e.g. √2 – of shares.
I am guilty of that too. It gives me some kind of mental peace I guess.
I am affected, too. As a Mustachian though, I never cared to spend money for a professional confirmation 
free Gemini says:
”Obsessive-Compulsive Disorder (OCD) is a mental disorder characterized by recurrent, unwanted thoughts and urges (obsessions) and repetitive behaviors or mental acts (compulsions) that the person feels driven to perform in response to an obsession or according to rigid rules.
The desire for extreme order, symmetry, and “just right” feelings is a well-known dimension of OCD, often referred to as Symmetry OCD or Ordering and Arranging Compulsions. This directly accounts for the need for perfectly sorted cupboards and overall order.
The need for round numbers is a form of compulsive behavior that is also often classified under OCD, specifically sometimes called Arithmomania (a compulsion to count or fixate on numbers) or an aspect of the “just right” feeling. An individual might feel severe anxiety if their stock portfolio holdings, investment amounts, or other numbers aren’t perfectly round, even if they know it is irrational. The distress is what separates this from mere preference.”
How can you guys manage the fact that the values nearly never show even numbers?
My irrational investment habits are checking the value of my investments too frequently (more then say once a month) and reading threads on this forum discussing investment habits I disagree with (stockpicking and market timing).
On a more general financial management note: obsessing over the price of a new subscription/service/insurance when I sign on and then never changing it for a better offer once I have the service going.
What prompt did you use, precisely? 
“which mental disorder thrives on order in real world, sorted items in a cupboard and round numbers in stock protfolio. Give several options and narrow in on most likely candidate”
The other options didn’t sound any better :
I started to feel better after I got rid of fractional shares of ETFs.
That’s a little disappointing to hear … I thought you were only holding shares in multiples of π.
I miss the good old times stocks where quoted in 1/8th. It is only 25 years with the decimal system on the New York stock markets…
shaking head - I check the value of my portfolio multiple times a day… and find myself even doing this during the weekend when the markets are closed (well, except for Bitcoin I guess); not proud of it, probably not good for my mental health… but I can’t help myself…
regarding values not showing even numbers… this is one (somewhat subconscious) reason to go for round share numbers… especially 10 / 100 / 1000 / 10000… because then there’s a very elegant link between share price and total value of the position - i like the fact that when you have 1000 of a certain stock and say it rises by 1 USD that you know that translates into a full 1000 USD for your position
I should add that when it comes to options there’s something which really annoys me… sometimes company’s do a capital return and then the options count (i.e. underlying shares) or strike price gets adjusted. It’s not just annoying from an esthetics perspective but can in fact also lead to exposures. I have one such case right now… I wrote a covered call but am now not fully covered anymore due to adjustments to the options mid-process.
(starts venting) Almost like the little greeting from the kitchen, I sometimes receive stocks from another company (through splits or stock dividends). It’s mostly a minuscule position and I never asked for it and then I have to spend unnecessary time for position keeping (in Excel) and selling it. Of course, I could keep it but then the order of what I planned to own has been negatively impacted. Must be OCD. (stops venting)
We’re on a roll here.
A rather major annoyance for me is that (with my bank at least) I can’t categorize my positions so I can track strategies separately.
E.g. put all my ETF’s in one big ETF bucket and measure returns. Have a different bucket with growth stocks, a different with dividend yield, and also seperate out options positions in a bucket so they do not pollute my overall view.
My irrational habits are:
So my portfolio is
CH Large (SPI): 25.00%
CH Small/Mid (SPI Extra): 25.00%
US (VTI): 35.00%
EM (IEMG): 15.00%
Let’s be serious, we want reporting to cover different custodians, potentially 3a providers and physical assets anyways, so a single broker will never be able to deliver for us… I have put so much work into my consolidated reporting spreadsheet, it is insane. If Saxo or IBKR ever change their csv export formats, I will have to liquidate my portfolio.