A single year's raise can mask a longer real-wage trend.
Even when individual years looked roughly acceptable.
Circle of competence means the actual multi-year numbers, not a general impression.
Know the Trend, Not Just This Year's Number
Charlie Munger's published circle-of-competence principle draws a line between what someone genuinely understands and what merely sounds familiar, and circle of competence applied to understanding your own real wage trend tests whether a household actually calculates its multi-year, inflation-adjusted income change, or just assumes recent raises have kept pace. For example, consider a household whose nominal income rose 12% over four years, from $72,000 to $80,640, which sounded reasonable in isolation. Cumulative inflation over the same period ran 14.5%, meaning the household's real purchasing power actually declined by roughly 2.1%, a fact obscured by the fact that no single year's raise looked obviously inadequate on its own. Per the USC archive of Munger's psychology speech, Munger's published work repeatedly examined how a single, isolated data point can look acceptable while a longer, cumulative pattern tells a different story, which is exactly what comparing multi-year nominal growth against cumulative inflation reveals. As of July 2026, this is especially important if you've never calculated your income's actual multi-year trend against cumulative inflation over the same period.
Each individual raise looked acceptable. The 4-year trend reveals a real decline.
Calculate the Multi-Year Trend, Not Just This Year
Per the Berkshire Hathaway letter archive, evaluating a number through genuine, verified data rather than a comfortable assumption was treated as essential to sound judgment. Comparing your income trend against the national average of 0.38% APY on any FDIC-insured savings built from that income, alongside CFPB resources on cost of living, keeps the fuller financial picture honest.
| Check | What it reveals | Next check |
|---|---|---|
| Single year's raise versus that year's inflation | A partial, potentially misleading snapshot | Extend the comparison across 3-5 years |
| Multi-year nominal growth versus cumulative inflation | The genuine real-wage trend | Calculate this directly from pay records |
| Real decline found despite individually acceptable years | A pattern worth addressing directly | Consider a larger ask or a role change |
| Genuine multi-year real gain confirmed | Purchasing power growing as assumed | Continue monitoring periodically |
Calculating your multi-year real wage trend has real benefits: it reveals a pattern that individual year-by-year comparisons can hide entirely. The risk of only checking a single year at a time, as the four-year example shows, is missing an accumulated real decline while each individual raise looked acceptable. However, that said, it depends on the specific years compared to a longer average: a single unusually strong or weak year can distort a short window, so a slightly longer trend, 3-5 years, gives a more reliable picture than any single comparison. If you're deciding whether your income has genuinely kept pace, choose to trust a single year's comparison only if you've also confirmed the multi-year trend agrees with it; choose to calculate the fuller multi-year trend if you haven't checked it before. This is when this matters most: at least once every few years, not only when a single raise feels disappointing.
3-5 years of nominal growth against cumulative inflation.
Individually acceptable years can still add up to a real decline.
Pull actual pay history rather than estimating from recollection.
Recalculate every few years as your income and inflation both change.
When This May Not Apply
A household that has already calculated its multi-year real wage trend and confirmed it's genuinely positive doesn't need to redo the exercise until a meaningful amount of time has passed. This is especially important to distinguish from simply feeling confident without having actually run the calculation.
What to Do Next, in 20 Minutes
- Pull your actual income for the past 3-5 years from pay records or tax filings.
- Calculate your total nominal income growth over that period.
- Compare it against cumulative inflation over the same years.
- Read a mental model for judging whether a raise actually beats inflation and inflation is a household purchasing power problem for related frameworks.
- Read how does inflation affect your money for background on the mechanism.
- Run a full Money Map check to see this alongside your full financial picture.
Sources and Methodology
This article applies Charlie Munger's published circle-of-competence principle to household real-wage-trend calculation. It is educational and does not constitute personalized financial or tax advice.
- USC Munger speech archive· Checked 2026-07-10
- Berkshire Hathaway letters· Checked 2026-07-10
- Consumer Financial Protection Bureau consumer tools· Checked 2026-07-10
- SwitchWize methodology· Checked 2026-07-10
Next scheduled verification: 2026-10-10
Educational content from the SwitchWize Research Desk. Charlie Munger and related entities are not affiliated with or endorsing SwitchWize.
Connect the lesson
Turn the article into a next step.
Switchwize takeaway
Protect the base first.
Review cash, debt, fees, and product fit before chasing the next financial upgrade.
Calculate my own multi-year real wage trend →Frequently asked questions
Why calculate a multi-year real wage trend instead of just this year's raise?+
Isn't checking this year's raise against inflation enough?+
How do I calculate my own multi-year real wage trend?+
Disclaimer
This article is educational and does not provide personalized investment, tax, legal, or financial advice. Charlie Munger, the Munger estate, Berkshire Hathaway, and related entities are not affiliated with or endorsing SwitchWize. References to public letters, speeches, and books are used for educational interpretation only.