Inflation is not a headline — it's your credit-card statement. The "CPI" comes out as a single number, but beneath it lives a weighted average of thousands of items. If your spending doesn't match the average basket, your felt inflation won't either.
Why lived inflation differs from the index
The index is an average; you buy a specific basket. The gap between the two isn't a lie — it's a mix mismatch.
- High rent share → you feel housing spikes more than the average.
- Long commute → you feel oil spikes more.
- Kids in school → tuition inflation lifts your felt number.
- Frequent tech upgrades → deflating categories can dampen your felt rate below the headline.
Nominal vs. real
The biggest household-level miss is confusing nominal and real amounts. A 3% pay raise is negative in real terms when prices rise 5%. When you see "record wages" in the news, make a habit of checking whether that's nominal or real.
Why the Big Mac Index is charming
The Big Mac Index is an intuition tool, not an academic one. Converting a single burger's local price into USD gives a quick read on whether a currency looks under- or over-priced relative to purchasing power. Its weakness: labor, rent, and tax structures differ so much by country that a single item can bias the comparison. The Economist also publishes a GDP-adjusted version for exactly that reason.
A short practice checklist
- What are your three biggest spending categories right now?
- Do you roughly know how each of the three has moved in the last 12 months?
- If your felt inflation differs from CPI, where is the gap coming from?
- Has your income grown faster or slower than CPI?
- When you compare across years, are you aligning FX and tax bracket?