Finlume
Smarter decisions about money — practical, evidence-based finance guides.
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The 4% Rule by Retirement Year, 1928–1996: Who Ran Out?
We tested the 4% rule for every US retirement year from 1928 to 1996. It failed for four, all from 1965–69. The worst year to retire was 1966, not 1929.
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Stock Market Crash Recovery Time After Inflation and Dividends
Six S&P 500 crashes recomputed with dividends and inflation. The 1973 and 2000 recoveries took about 12 years in real terms, not 7. Primary data, monthly averages.
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Gold vs. Stocks After Inflation, 1971–2025
From 1971 to 2025, gold returned 4.96% a year after inflation versus 6.96% for US stocks, and took 28 years to regain its 1980 dollar peak. Primary data.
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How Much of the S&P 500's Return Came From Dividends?
Price-only vs. total return for every decade since 1930, from primary data. Dividends were 36% of the nominal return since 1928 and about half after inflation.
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How Long Do You Have to Hold the S&P 500 to Avoid a Loss? 98 Years of Data
Every 1- to 30-year holding period of the S&P 500 from 1928 to 2025, computed from primary data: how often each one lost money, the worst and median outcomes, and why inflation stretches the safe horizon from 16 years to 18.
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Stocks vs. Bonds vs. Cash: How Often Each Won, 1928–2025
Every 1- to 30-year window since 1928: how often US stocks beat bonds and cash, and how often the 'safe' assets lost purchasing power. Primary data.
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Calendar or Drift? How to Optimize Your Rebalancing Schedule
Should you rebalance monthly or once a year? Vanguard's 88-year simulation shows frequency barely matters — your band rule (absolute vs. relative) does.
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Lean, Fat, or Barista: Which FIRE Strategy Fits Your Goals?
Lean and Fat FIRE share the exact same 25x multiplier — only your spending base differs. Barista FIRE changes the formula entirely. Here's how to choose.
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Stop Draining Your Emergency Fund for Planned Expenses
If your emergency fund keeps shrinking, it's rarely about saving too little — it's mixing planned expenses with true emergencies. Sinking funds fix that.
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Real vs. Nominal Returns: Calculating Your True Growth
Your statement says 8% — but inflation ate part of it. Learn the quick approximation vs. exact Fisher equation, with an error table by inflation level.
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How Much of Your Portfolio Should Be in a Single Stock?
How much of your portfolio should sit in one stock? Industry thresholds, the disposition effect, and Bessembinder's data on how rarely single winners pay off.
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Cash vs. Margin Brokerage Accounts: Which Should You Open?
Cash and margin accounts aren't a checkbox — they're a risk contract. Here's the structural difference in settlement, buying power, and forced liquidation.
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Finding the Break-Even Point on Your Insurance Deductible
A higher deductible lowers your premium, but it only pays off after enough claim-free years. Here's the break-even formula, with two worked examples.
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Personal Loan vs. Credit Card: Financing Large Purchases
Personal loan or credit card for a big purchase? Which is cheaper depends on your payoff timeline — see the real cost comparison and crossover point.
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Why Copying a Billionaire's Stock Picks Doesn't Work
A famous investor bought a stock, so you bought it too. Here's why the filing is weeks old, the context is missing, and your position size never matches theirs.
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How Accurate Are Analyst Price Targets? The Answer Depends on the Definition
Analyst price targets look precise, but 'accurate' varies by definition. Here's what hit-rate research actually shows — and how to read it.
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3% vs 4% vs 5%: How Long Will Your Retirement Portfolio Actually Last?
Does 3%, 4%, or 5% actually last 30 years? A data-driven comparison across retirement horizons and countries, plus what a 1-point difference costs you in years.
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The True Cost of Pausing Your Retirement Contributions for 2 Years
A 2-year savings pause early on costs about 7x more than the same pause right before retirement. Here's the math, and the catch-up cost.
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Why Getting the Trend Right Still Doesn't Make You Money
Correctly predicting the next big industry doesn't guarantee a profit. Here's why thematic investing can fail even when the forecast is right.
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US-Only vs Global Portfolios: Does International Diversification Pay?
Is the S&P 500 alone enough? Home-bias data, the 2000s lost decade, and the 2025 reversal — what the numbers say about diversifying globally.