Topic
Fundamentals
14 articles
How much do investment fees actually cost you? The number is 17% of your retirement.
The average fund investor now pays 0.32% a year, down from 0.80% two decades ago. If you still pay 1%, the compounding difference over a 30-year savings life is about $99,000 on a $180,000 contribution schedule — roughly 17% of the final balance.
How long do you have to hold stocks to not lose money? We ran every window since 1928.
Over 98 years, no 20-year holding period in the S&P 500 lost money in nominal terms. But adjust for inflation and 11% of 10-year periods lost purchasing power — with the worst down 34%. The usual answer is right for the wrong reason.
Does trading more often hurt your returns? 66,465 households say yes.
The definitive study tracked every trade in 66,465 brokerage accounts for six years. The most active traders earned 11.4% a year while the market returned 17.9% — and the average household turned over 75% of its portfolio annually to underperform by 1.5 points.
Does rebalancing improve returns? We tested 98 years — it cost 1.1 points a year.
A 60/40 portfolio rebalanced annually since 1928 grew to $257,108. The identical portfolio left alone grew to $697,640. Rebalancing lost money — and it is still the right thing to do, for a reason that has nothing to do with returns.
What is the average stock market return? We ran 98 years of data — the answer is 10%, 6.8%, or neither.
We computed it from the raw annual series: 11.86% arithmetic, 10.02% compounded, 6.79% after inflation. And in 98 years, only four landed anywhere near the average — which is the finding that actually matters for planning.
What percentage of fund managers beat the index? The 15-year number is brutal.
Over 15 years, 89.5% of active large-cap US funds failed to beat the S&P 500. Professionals with research teams and Bloomberg terminals lose this bet nine times in ten — which should change how you think about your own stock picking.
Do investors really underperform their own funds? The famous number is disputed.
Morningstar says bad timing costs investors 1.2 percentage points a year — about 15% of their funds' returns. A 2026 paper in the Financial Analysts Journal says that figure is largely a statistical artifact. Both matter.
Do stop-losses actually work? What they protect and what they cost
A stop-loss is a good tool wearing a misleading name. It caps a trade, not a risk — and for long-term investors it usually sells the exact thing they should be holding.
How to write an investment thesis (in ten minutes, with a template)
A thesis isn't a research report. It's a short, falsifiable note to your future self — the only thing standing between you and a portfolio of positions nobody remembers buying.
Index funds vs individual stocks — how to actually decide
The honest framing isn't "which one wins." It's what each one costs you in attention, and whether you have evidence you can spend that attention well.
When should you sell a stock? The four honest reasons
Almost everyone has a buying process and no selling process. That asymmetry is where most of the damage happens — here are the only four reasons to sell that survive scrutiny.
Dollar-cost averaging vs lump sum — the honest answer
Lump sum wins more often on the math. Dollar-cost averaging wins more often in practice. Both statements are true, and the gap between them is the whole point.
How many stocks should you actually own?
The honest answer for most people is a number between 1 and 25, and which end you land on depends less on math than on how much attention you can genuinely give.
Time in the market vs timing the market — what the phrase actually means
"Time in the market beats timing the market" is repeated so often it has stopped meaning anything. Here's the real mechanism behind it, and the one case where it's misleading advice.
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