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Built-in Inflation Explained

Built-in inflation is the component of inflation that persists due to past inflation becoming embedded in expectations and economic behavior. It's sometimes called inflation inertia or momentum inflation. Even if the original causes of inflation disappear, built-in inflation keeps prices rising because workers expect inflation and demand higher wages, businesses expect inflation and raise prices preemptively, and lenders expect inflation and demand higher interest rates. These expectations create a self-fulfilling prophecy where expected inflation becomes actual inflation.

Quick definition: Built-in inflation is the inflation that persists due to inflation expectations being embedded in wage and pricing decisions, creating momentum even after original inflation sources fade.

This type of inflation is particularly troublesome because it's self-perpetuating. Once inflation expectations become entrenched, they're difficult to dislodge. Even if a central bank solves the underlying demand-pull or cost-push problem, built-in inflation continues until expectations adjust. This is why central banks place enormous emphasis on maintaining low inflation expectations—if people expect 2% inflation and make wage and pricing decisions based on that expectation, actual inflation stays around 2% even without active policy support.

Key takeaways​

  • Built-in inflation stems from inflation expectations becoming embedded in wage and pricing decisions.
  • It persists even after original inflation causes disappear, creating momentum.
  • The three sources of inflation (demand-pull, cost-push, and built-in) interact and reinforce each other.
  • Inflation expectations are forward-looking—people base current decisions on expected future inflation.
  • Central banks prioritize maintaining low inflation expectations because it's crucial for controlling inflation.
  • Breaking high inflation expectations requires both low actual inflation and credible central bank commitment to price stability.
  • The "sacrifice ratio" measures how much recession is needed to reduce inflation expectations.

How inflation expectations work​

Inflation expectations fundamentally shape economic behavior. When a worker negotiates a wage increase, they consider expected inflation. If they expect 4% inflation over the next year, they'll demand at least a 4% raise to maintain purchasing power, plus any additional raise reflecting their productivity or market conditions. If they expect 2% inflation, they'll demand less.

Similarly, businesses setting prices consider expected inflation. If a retailer expects 3% inflation over the next year, they might raise prices now in anticipation of higher input costs later. If they expect 1% inflation, they'll raise prices less. Lenders consider expected inflation when setting interest rates. If they expect 4% inflation, they'll charge interest rates 4 percentage points higher to compensate for inflation eroding loan repayment value.

These expectations become self-fulfilling. If workers demand 4% raises based on expected 4% inflation, and businesses raise prices 4% based on expected 4% inflation, then actual inflation will indeed be around 4%. The expectation creates the reality. This is built-in inflation—the inflation that stems from expectations rather than from current excess demand or cost shocks.

Crucially, inflation expectations are forward-looking, not backward-looking. Workers don't decide on wage increases based on last year's inflation; they base decisions on expected inflation over the next year. This is why central banks can't wait for inflation to appear in data before responding. By the time inflation is visible in recent data, expectations might already be building, making future inflation likely regardless of current economic conditions.

The Phillips Curve and inflation expectations​

The Phillips Curve originally described an inverse relationship between unemployment and inflation. Lower unemployment meant higher wage pressure and thus higher inflation. Higher unemployment meant lower wage pressure and lower inflation. This relationship held fairly well from the 1950s through the early 1970s.

However, in the 1970s, stagflation broke the Phillips Curve relationship. High unemployment coexisted with high inflation, contradicting the theory. Economists eventually realized that inflation expectations explained the breakdown. The Phillips Curve still worked, but it shifted based on inflation expectations.

Here's the modern understanding: the Phillips Curve shows the relationship between unemployment and inflation given inflation expectations. When inflation expectations are low, the curve is positioned to show that low unemployment produces only modest inflation. When inflation expectations are high, the same low unemployment produces much higher inflation.

This distinction explains 1970s stagflation. Inflation expectations rose due to high actual inflation in the early 1970s. Once expectations were elevated, high inflation persisted even as unemployment rose during recessions. The policy problem became not just controlling current inflation but anchoring inflation expectations downward.

Inflation's three sources and their interaction​

Economists typically identify three sources of inflation: demand-pull (excess aggregate demand), cost-push (rising production costs), and built-in (inflation expectations). These three interact and reinforce each other.

Suppose demand-pull inflation emerges from excessive monetary expansion. Prices start rising from excess demand. Workers notice prices rising and demand higher wages to maintain purchasing power. Businesses, seeing both rising demand and rising wages, raise prices further. Expectations of future inflation become embedded. Even if the central bank reduces money growth, stopping the original demand-pull, the wage and price increases continue because expectations remain elevated. Built-in inflation persists.

Alternatively, cost-push inflation might originate from oil price shocks. Costs rise, prices rise, workers demand wage increases to offset rising prices. Businesses and workers begin expecting persistent inflation. Once expectations are elevated, wage and price pressures continue beyond the original oil shock. Built-in inflation becomes a major driver.

Breaking this cycle requires addressing all three sources. Demand must be controlled (monetary and fiscal policy), costs must stabilize (supply-side improvements), and expectations must be anchored (credible commitment to low inflation). Failure on any front allows inflation to persist.

How central banks manage inflation expectations​

Central banks have learned that managing inflation expectations is as important as managing current inflation. If expectations are well-anchored (everyone expects low inflation), actual inflation stays low naturally. If expectations become unanchored (people expect high inflation), actual inflation will be high regardless of policy.

Central banks manage expectations through several mechanisms:

Credibility is foundational. If the central bank has a track record of maintaining low inflation, people expect low inflation and make wage and price decisions accordingly. If the central bank has a history of allowing inflation to drift higher, people expect inflation and demand wage increases to compensate, perpetuating inflation. Building credibility takes years; losing it takes moments.

Forward guidance communicates future policy intentions. When a central bank credibly commits to specific inflation targets and explains how it will achieve them, people adjust expectations. If the Fed says inflation will be 2% and demonstrates commitment through consistent policy, expectations move toward 2%, which helps actual inflation move toward 2%.

Transparency about inflation targets and policy frameworks helps anchor expectations. The Federal Reserve publicly states its 2% inflation target and explains its framework for monetary policy. This transparency helps people predict future policy and adjust expectations accordingly.

Actual inflation control is necessary to maintain credibility. If a central bank claims to target 2% inflation but allows 5% inflation, credibility erodes, and people stop believing low inflation expectations. Central banks must actually deliver low inflation to maintain inflation-expectation anchoring.

Inflation targeting as a policy regime has been adopted by most developed-country central banks specifically because it helps anchor expectations. By stating a specific numerical target (usually 2%) and using policy to achieve it, central banks signal commitment and help coordinate expectations around that target.

Built-in inflation as inflation momentum​

Built-in inflation creates momentum. Even if the underlying demand-pull or cost-push cause is resolved, inflation continues because of established expectations and commitments. A company that signed a contract committing to specific price increases must follow through. A labor contract committing to wage increases must be honored. These commitments create inflation momentum.

This momentum explains why breaking high inflation is difficult. In 1979–1982, Fed Chair Paul Volcker needed to raise interest rates sharply (pushing the federal funds rate above 20% at times) to break inflation expectations. The Fed essentially had to prove through painful high unemployment that it was serious about low inflation. Once inflation expectations finally shifted, inflation gradually came down, but the process took years and created a severe recession.

The sacrifice ratio quantifies this momentum effect. It measures how much reduction in output is needed to reduce inflation by one percentage point. A sacrifice ratio of 2 means a 4% reduction in output is needed to reduce inflation by 2 percentage points. High inflation with entrenched expectations has a high sacrifice ratio—controlling it requires painful economic slowdown. Low inflation with well-anchored expectations has a low sacrifice ratio—controlling it requires less economic cost.

Real-world examples​

The 1970s United States provides the classic example of built-in inflation. Initial oil shocks (cost-push) pushed inflation upward. But the bigger problem was that inflation expectations became unanchored. Workers who experienced 10% inflation in some years expected continued high inflation. Labor contracts included automatic wage escalators, ensuring wage increases even if inflation fell. This contractual inflation created momentum.

The Federal Reserve initially tried to reduce inflation gradually, but with high expectations embedded in contracts and behavior, inflation persisted. A harsh breakthrough was required. Paul Volcker tightened policy dramatically, deliberately inducing the worst recession since the Great Depression (unemployment briefly exceeded 10%) to break inflation expectations. Only after sustained high unemployment and subdued inflation for several years did expectations adjust downward. The sacrifice ratio was severe: eliminating about 8 percentage points of inflation required roughly 25 percentage points of cumulative unemployment (unemployment of 6% for 4 years, for example).

The 1990s offers a contrasting example. When inflation rose above the Fed's comfort level in the mid-1990s, the Fed raised rates moderately. Expectations were well-anchored because the Fed had built credibility in the late 1980s and early 1990s. The rate increase was sufficient to control inflation without creating a severe recession. The sacrifice ratio was much lower. Expectations adjusted because people believed the Fed would maintain low inflation.

The 2020–2023 period provides a modern example of building then breaking elevated inflation expectations. Fiscal stimulus (government spending) and continued monetary accommodation despite rising inflation allowed expectations to become unanchored. By 2021, surveys showed households expected 4–5% inflation for the next year. Workers demanded higher wages. Businesses raised prices more aggressively. Built-in inflation accelerated. The Fed eventually tightened aggressively starting in 2022, but because expectations had become unanchored, the tightening was more severe than might have been needed earlier.

The role of central bank credibility​

Inflation expectations are only well-anchored if people believe the central bank will maintain price stability. If the central bank frequently allows inflation to exceed its stated target, expectations become unanchored. If the central bank credibly commits to maintaining inflation around target, expectations remain anchored and inflation stays close to target.

The European Central Bank faced this credibility challenge in the 2010s. Some countries had high inflation histories and low credibility. The ECB's adoption of explicit inflation targeting and consistent policy helped anchor expectations in these countries over time. As the ECB proved itself committed to 2% inflation, expectations gradually moved toward that target.

Central bank independence is relevant here. A central bank controlled by politicians who want short-term stimulus is less credible than an independent central bank focused on long-term price stability. Countries with dependent central banks often face higher inflation and less anchored expectations. The Federal Reserve's independence from the Treasury and Congress helps maintain its credibility for inflation control.

Built-in inflation and wage-price spirals​

Built-in inflation frequently manifests as wage-price spirals—a self-reinforcing cycle where rising prices cause workers to demand higher wages, which increases business costs, which increases prices, which triggers further wage demands.

A wage-price spiral is particularly dangerous because it becomes difficult to break without high unemployment. Each party (workers seeking wage growth, businesses seeking profit maintenance) has an incentive to continue the spiral. Breaking it requires either inflation falling sharply (reducing workers' wage demands and businesses' pricing pressure) or unemployment rising enough that workers lose bargaining power and stop demanding wage increases exceeding productivity growth.

The 1970s stagflation partially reflected wage-price spirals. Labor unions were strong and could enforce wage increases even during recessions. Wage contracts with automatic escalators (wage increases tied to inflation) guaranteed rising wages regardless of demand conditions. These institutional features made the wage-price spiral particularly intractable. By the time recessions hit, wages were already committed to rising. Cost-push inflation persisted despite weak demand.

Common mistakes​

Mistake 1: Underestimating expectations. Some people think inflation is purely mechanical—if demand is weak and inflation is falling in recent data, inflation will continue falling. But if expectations are rising, future inflation will pick up regardless of current conditions. Expectations matter as much as current economic conditions.

Mistake 2: Assuming expectations adjust instantly. In economic models, expectations adjust quickly. In reality, they adjust slowly. If inflation is 2% for a year, people don't immediately expect 2% ongoing—it takes multiple years of consistent 2% inflation for expectations to fully adjust toward 2%. This sticky expectation adjustment is why central banks emphasize credibility and forward guidance.

Mistake 3: Believing expectations can be shifted by communication alone. Central bank statements and forward guidance matter, but only if backed by actual policy consistency. Empty promises of low inflation don't anchor expectations if the central bank doesn't deliver low inflation. Credibility requires both communication and actions.

Mistake 4: Forgetting that inflation expectations are heterogeneous. Different people have different inflation expectations. Economists and financial markets might expect 2% inflation based on Fed forward guidance. Workers in strong bargaining positions might expect 4% based on their recent wage gains. Longer-term expectations might differ from short-term expectations. Aggregating these different expectations obscures the reality that expectations vary widely.

Mistake 5: Ignoring institutional factors in wage setting. In economies with strong labor unions and industry-level wage bargaining (like Germany or Scandinavia), wages are set more by institutional processes than by individual market negotiations. In these settings, once wage expectations are set high, inflation persists even if demand weakens because wage negotiations are determined by precedent and institutional relationships, not current demand conditions.

FAQ​

How do economists measure inflation expectations?​

Multiple approaches exist. Surveys ask households and businesses about expected inflation (e.g., "What inflation do you expect in the next year?"). Financial markets reveal expected inflation through breakeven inflation rates—the difference between nominal Treasury yields and TIPS (inflation-protected Treasury) yields. If nominal 10-year Treasuries yield 3% and TIPS yield 1%, markets expect 2% inflation. Economists also extract expectations from economic models fitted to recent data. Each approach has limitations; the best practice is to examine multiple measures.

Can inflation expectations ever be too low?​

Yes. If people expect deflation or very low inflation (say, zero or negative), they postpone purchases, hoard cash, and demand very high wages to compensate. This can become self-fulfilling, creating actual deflation. The 2010s Japanese economy faced this challenge—expectations of low inflation became entrenched, making actual inflation difficult to achieve despite aggressive central bank easing. Central banks want expectations anchored around a modest positive inflation (2%), not deflation.

Is wage growth always due to inflation expectations?​

Not entirely. Wage growth can reflect rising productivity (workers are more productive, so higher pay is justified), tight labor markets (shortage of workers pushes wages up), or skill-biased demand (certain skills are scarce and command high wages). However, in sustained inflation periods, inflation expectations become a significant driver of wage demands.

How do asset prices relate to inflation expectations?​

Asset prices reflect expected inflation in multiple ways. Nominal asset prices (stocks, real estate) tend to keep pace with inflation if real returns remain constant. Nominal interest rates reflect expected inflation plus real interest rates. Gold and commodities often rise when inflation expectations rise because they're viewed as inflation hedges. Changes in asset prices can reveal shifts in inflation expectations.

Can central banks control inflation expectations completely?​

No. Central banks can influence expectations through credibility and policy, but they can't control them completely. Expectations depend on many factors outside central bank control: oil prices, geopolitical shocks, fiscal policy, labor market conditions, and media narratives all influence expectations. Central banks can anchor expectations around their target but can't eliminate all expectation shifts.

What happens if inflation expectations are anchored too low?​

If expectations are anchored below the central bank's actual target, there's a persistent gap. The Fed might target 2% inflation but if expectations are anchored at 1%, and central bank policy delivers around what expectations warrant, actual inflation will be 1%. This creates a credibility problem—is the central bank's 2% target real or just talk? Most central banks would rather have expectations slightly above target than below.

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Summary​

Built-in inflation is the inflation that persists due to inflation expectations being embedded in wage and pricing decisions. It creates momentum that continues even after original inflation sources disappear. Central banks manage built-in inflation by maintaining credibility, anchoring inflation expectations, and delivering consistent low inflation. Once expectations become unanchored upward, breaking inflation requires either painful macroeconomic slack or a credible policy shift. Understanding built-in inflation's role explains why central banks prioritize expectations management and why breaking high inflation is more difficult than simply managing current demand and supply conditions.

Next​

→ The wage-price spiral