Inflation: Causes, Measurement, and Market Impact
Inflation is the sustained increase in the general price level of goods and services. It is arguably the most important macroeconomic variable for traders and investors.
Types of Inflation
Demand-Pull Inflation
- Too much money chasing too few goods
- Caused by excessive consumer spending, government stimulus, or credit expansion
- Classic example: Post-COVID stimulus checks
- Central banks combat this by raising interest rates
Cost-Push Inflation
- Rising production costs push up prices
- Supply chain disruptions, commodity price spikes, wage increases
- Example: 2022 energy crisis raising costs across all industries
- Harder for central banks to address without causing recession
Monetary Inflation
- Excessive growth in money supply
- Central bank printing money (quantitative easing)
- Government deficit spending financed by money creation
- Often has a lag of 12-18 months before showing up in prices
Asset Price Inflation
- Not captured in traditional CPI
- Stock market bubbles, housing price surges
- Can exist alongside low consumer price inflation
- Creates wealth inequality and financial instability
How Inflation is Measured
Consumer Price Index (CPI)
- Most widely watched inflation measure
- Basket of goods and services weighted by consumer spending
- Headline CPI includes food and energy
- Core CPI excludes food and energy (more stable)
- Released monthly in most countries
Producer Price Index (PPI)
- Measures prices at the producer/wholesale level
- Leading indicator for CPI (producer costs flow to consumers)
- Pipeline of inflationary pressure
- Markets watch for surprises versus consensus
PCE (Personal Consumption Expenditures)
- The Fed's preferred inflation measure
- Broader than CPI and accounts for substitution effects
- Core PCE is the Fed's primary inflation target (2%)
- Released monthly by the Bureau of Economic Analysis
How Inflation Affects Markets
Currencies
- High inflation weakens a currency (purchasing power declines)
- BUT: If central bank raises rates aggressively to fight inflation, currency can strengthen
- The net effect depends on real interest rates (nominal rate minus inflation)
- Currencies with positive real rates tend to strengthen
Bonds
- Rising inflation is negative for existing bonds
- Bond prices fall when inflation exceeds expectations
- Investors demand higher yields to compensate for inflation
- TIPS (Treasury Inflation-Protected Securities) offer protection
Stocks
- Moderate inflation (2-3%) is generally positive for stocks
- High inflation compresses valuations (higher discount rates)
- Companies with pricing power outperform during inflation
- Real assets (commodities, real estate stocks) tend to outperform
Commodities
- Inflation is generally positive for commodity prices
- Commodities are real assets whose value rises with prices
- Gold is the traditional inflation hedge
- Energy and agricultural commodities benefit directly
The Phillips Curve and Tradeoffs
The Traditional View
- Lower unemployment leads to higher inflation (and vice versa)
- Central banks must balance these two goals
- Rate hikes fight inflation but raise unemployment
- Rate cuts boost employment but risk inflation
The Modern Reality
- The relationship has weakened over recent decades
- Inflation can be low even with low unemployment (2010s)
- Supply shocks can cause both high inflation AND rising unemployment (stagflation)
- Central banks face difficult choices when the tradeoff breaks down
Key Takeaways
- CPI and PCE data releases are among the most important economic events
- Inflation affects every asset class differently
- Real interest rates (nominal minus inflation) are what truly matter
- Central bank responses to inflation move markets more than inflation itself
- Understanding the type of inflation helps predict its persistence and policy response