Price history is loading. Model lines are illustrations, not price targets or floors. Power law model attributed to Giovanni Santostasi. Not investment advice.

Three ideas

Reading a model critically.

Model line

This illustration uses time raised to the 5.68 power. Its output is a model estimate, not fair value.

Lower model line

Drawn at 0.42 × the model line. This is a chosen multiplier, not a guaranteed price floor.

Monetary systems

Inflation changes purchasing power. Compare historical data, assumptions, and measurement periods before drawing conclusions. BLS CPI Inflation Calculator, Jan 1971 → Jul 2026.

Model line = 10^−16.493 × days^5.68
Lower line = 0.42 × model line

The time variable counts days from January 2009. A mathematical fit does not establish causation, future returns, or a reliable lower bound.

Power law model per Giovanni Santostasi — not investment advice.

Why it matters

Purchasing power over time.

1971–2026

Purchasing power, illustrated. Rounded estimates; not a live CPI feed.

For an official historical comparison, use the BLS CPI Inflation Calculator (Jan 1971 → Jul 2026) — not investment advice.

Put ideas into practice.

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