Real Return ≈ Nominal Return − Inflation
Cash in a 0%-interest savings account during 3% inflation LOSES 3% of purchasing power per year — even though the dollar number doesn't change. Inflation is the silent tax on savers who do nothing. The cure is not stuffing money under a mattress; the cure is owning assets whose value tends to rise with prices — index funds, real estate, and inflation-protected bonds (TIPS) all qualify. Compounding (from pf-2) and inflation are the two forces that decide whether your future self is richer or poorer in real terms.
Headline CPI is a single number, but your personal inflation rate depends on what you buy. Healthcare inflation typically runs around 5% per year while consumer electronics often deflate (prices fall) around 3% per year. If you spend heavily on healthcare and lightly on electronics, your personal inflation rate is higher than the headline. For the macro framing — how the Fed measures and responds to inflation — see mac-1 'Inflation: What It Is and Why It Matters'. For the value-investor view on holding cash during inflationary periods, see pfvi-7 'Inflation and the Cost of Holding Cash'.
Sit with the ideas.
Maya keeps $20,000 in a high-yield savings account paying 4.5% APY. CPI inflation is running at 3.2% per year. After one year (assume she doesn't deposit or withdraw), what is the real change in her purchasing power, and what is her account balance?