Blog

Writing on how dollar-cost averaging actually behaves, what dividend reinvestment is worth, and where backtests mislead. Where a claim can be measured, these posts measure it with the same simulation engine the calculator uses rather than describing the mechanism and leaving it there.

Why IRR and CAGR Give Different Answers for the Same DCA Plan

Two 'annualized return' numbers for the identical plan, arriving at very different percentages. Here's exactly why, and which one you should trust.

5 min read

Dollar-Cost Averaging vs. Lump Sum: What the Math Actually Says

The lump-sum-wins-more-often-on-average argument is true, and mostly beside the point. What actually determines which approach is right for you.

5 min read

What Dividend Reinvestment Is Really Worth Over 10+ Years

DRIP's effect looks small in year one and enormous by year fifteen. The mechanism behind that curve, and when it matters least.

4 min read

The S&P 500's Lost Decade: Investing Through 2000 to 2010

The S&P 500 absorbed two separate bear markets in a single decade. What a real DCA plan actually returned during that stretch, against a lump sum invested the same way.

4 min read

What Leveraged ETFs Would Have Done in a Real Bear Market

TQQQ launched in 2010 and has never lived through a multi-year bear market. What the daily-reset math actually implies about a decline like 2000 to 2002.

5 min read

Sequence of Returns Risk: Why Order Changes Your DCA Outcome

Two investors can contribute the same total amount and experience the same annual returns, in a different order, and end up with meaningfully different results. Here's the arithmetic.

4 min read

Why Backtests Can Mislead You

Survivorship bias, cherry-picked time windows, and the honest limits of a backtesting tool, including this one.

5 min read

Does It Matter Whether You Invest Weekly, Monthly, or Once a Year?

The same $72,000 into the same fund over the same decade, deposited on five different schedules. The annualized returns are nearly identical and the ending balances are not.

5 min read

What an Expense Ratio Actually Costs You Over 19 Years

Four mutual funds that all track the S&P 500, charging 0.02% to 1.59%. Same index, same contributions, same period, and a six-figure difference in what you end up with.

5 min read

The Same Plan, Eleven Different Starting Years

Identical contributions into the same fund for ten years, begun in eleven different years. Annualized returns range from negative four percent to nearly fifteen.

5 min read