Investing Articles
Compound interest, fees, contribution limits, dollar-cost averaging and Roth versus traditional, worked through with numbers.
A 0.75% Fee Difference Cost $29,000. Here Is the SEC Example
Investment fees are quoted in fractions of a percent, which makes them feel trivial. The SEC publishes an example showing exactly how untrivial they are over twenty years.
2026 Retirement Contribution Limits: 401(k) and IRA
The IRS raised both the 401(k) and IRA limits for 2026, and added a higher catch-up band for people aged 60 to 63. Here are the figures.
Compound Interest, Worked Out by Hand
Compound growth is quoted so often that it has stopped meaning anything. Working through the actual arithmetic is the fastest way to make it concrete again.
Dollar-Cost Averaging, and the Arithmetic Behind Why It Lowers Your Average Cost
Investing a fixed amount at regular intervals gives you an average cost below the average price. That is not a slogan; it is a property of averages, and here is the worked example.
Roth vs Traditional: The Two Are Identical Until One Thing Changes
If your tax rate is the same now as in retirement, Roth and traditional accounts produce exactly the same amount. Here is the proof, and the four things that break the tie.