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Inflation & real (after-inflation) returns
· Concept or strategy
Watch outA common mistake, trap or scam.
Inflation is the rise in prices over time; real return is what an investment earns after subtracting it.
See it on the Personal Finance & Estate map →How it works
Real return is roughly the stated return minus inflation. At 3% inflation, prices double in about 24 years; at 2%, about 36. Cash earning 4% with 3% inflation gains only 1% in buying power, and after federal and California tax it can lose ground. US consumer inflation peaked at 9.1% in June 2022; the Federal Reserve targets 2%. Stocks, real estate with rising rents, TIPS and I bonds have historically protected better than cash or fixed pensions.
Why it matters for you
Over a 30-year retirement, even moderate inflation can cut the buying power of a fixed income in half or more.
Think of it like
Like a long lease with no rent bumps: the rent stays flat while operating costs keep rising.
Red flags and protection
The Bureau of Labor Statistics' Consumer Price Index measures it, with data back to 1913; TIPS principal and I bond rates are tied to it.
Watch out for
Whether inflation settles near the Fed's 2% target or stays higher is debated; personal inflation, such as medical costs, differs by household.
Connections (2)
▸Inflation & real (after-inflation) returns works against Compound growth (time × return)Watch out
How they connect
Compounding in dollars overstates progress, because inflation compounds too. At 7% returns and 3% inflation, $1 grows to about $7.60 in 30 years, but only about $3.10 in today's buying power. Real returns are what fund future spending.
When it applies
Everywhere and always; acute in the US during the 1970s and again in 2021–2023.
How sure?
BLS CPI data and inflation-adjusted return series, such as Morningstar's SBBI, show the gap between nominal and real growth.
Watch out for
Future inflation is unknown; planners debate whether to assume 2.5%, 3% or more in long-range projections.
▸Cost-of-living adjustment (COLA) tracks Inflation & real (after-inflation) returnsLaw or rule (2026)
How they connect
The COLA follows the CPI-W, a government inflation index, so Social Security's buying power is protected, unlike most private pensions and annuities with fixed payments. It is one of the few truly inflation-adjusted incomes.
When it applies
The Bureau of Labor Statistics measures CPI-W monthly; SSA compares July–September averages with the prior year's each fall.
The rule
Published BLS data and SSA's COLA history let anyone check each year's adjustment against inflation.
Watch out for
The raise lags inflation by up to a year, as in 2022, and whether CPI-W reflects retirees' real costs is debated.