Level 2 - 4 min read

Inflation: The Silent Tax

CPI, purchasing power, and why cash sitting in a 0% account is losing value every single day, and what actually beats it.

Inflation is the rate at which prices rise over time. The practical consequence is that a dollar today buys less than a dollar did ten years ago. This isn't a bug in the economy: it's a structural feature. The question is what you do about it.

How CPI Works

The Consumer Price Index (CPI) tracks the price of a fixed basket of goods: housing, food, transportation, medical care, and others. When the Bureau of Labor Statistics says inflation is 3%, they mean this basket costs 3% more than it did a year ago.

The CPI is not perfect. It doesn't match your personal spending, it lags real prices, and the composition of the basket is regularly debated. But it's the official benchmark and the one that drives Federal Reserve policy and wage adjustments across the economy.

The Purchasing Power Math

At 3% inflation, the Rule of 72 says: 72 / 3 = 24 years for prices to double. Or equivalently, a $100 bill loses half its purchasing power in 24 years without you touching it.

At 4% inflation: prices double in 18 years. At 7% (as the US saw in 2022): prices double in roughly 10 years.

This matters for cash. Money sitting in a checking account earning 0% while inflation runs at 3% is actively losing value every year. The number on the screen stays the same. The purchasing power doesn't.

What Beats Inflation

  • Stocks: The S&P 500 has returned roughly 10% nominal (7% after inflation) over the long run. Historically the most reliable inflation beater for patient investors.
  • Real estate: Tends to track inflation or beat it modestly, and leverage amplifies returns further.
  • I Bonds and TIPS: Government bonds that adjust with inflation. Safe, but returns are modest.
  • High-yield savings accounts: Currently paying 4-5%, which can match or beat moderate inflation. Good for cash you need within a year or two.

Standard bonds with fixed coupons lose real value in high inflation. Long-term fixed-rate debt (like a mortgage locked at 3%) actually gets cheaper in real terms when inflation runs hot: you repay with dollars worth less than you borrowed.

Inflation is taxation without legislation. - Milton Friedman

Uncle Nobody: educational content, not financial, investment, tax, or legal advice. Just the math.

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