relationship between inflation and unemployment: traditional Phillips curve

📚 Links Between Macroeconomic Problems

In this lesson we explore how two big macro‑economic issues—inflation and unemployment—are connected. The classic way economists describe this relationship is the Phillips Curve. Think of it like a seesaw: when one side goes up, the other tends to go down.

🔍 The Traditional Phillips Curve

The original Phillips Curve, drawn by economist A. W. Phillips in 1958, showed a negative relationship between the rate of inflation (\$\pi\$) and the rate of unemployment (\$u\$) in the UK:

Unemployment (\$u\$)Inflation (\$\pi\$)
8%2%
6%4%
4%6%

The table shows that when unemployment falls, inflation tends to rise, and vice versa.

💡 Analogy: The Factory Line

Imagine a factory that produces gadgets. If the factory is running at full capacity (low unemployment), workers are busy and the cost of raw materials rises because demand is high. The factory passes these higher costs on to customers, so gadget prices go up—this is inflation.

If the factory slows down (high unemployment), workers have more free time, material costs fall, and gadget prices drop. Thus, the factory’s output level (unemployment) and the price level (inflation) move in opposite directions.

📈 The Expectations‑Augmented Phillips Curve

In the 1960s economists added a twist: people’s inflation expectations (\$\pi^e\$) matter. The new equation is:

\$\pi = \pi^e - \beta (u - u^*)\$

Where:

  • \$u^*\$ = natural rate of unemployment (the rate that doesn’t cause inflation to rise)
  • \$\beta\$ = how sensitive inflation is to the unemployment gap

If people expect higher inflation, the curve shifts upward. This explains why the original trade‑off broke down during the 1970s stagflation (high inflation + high unemployment).

⚙️ How Policymakers Use the Curve

  1. Monetary policy (e.g., raising interest rates) can push the economy up the curve, reducing inflation but increasing unemployment.
  2. Fiscal stimulus (e.g., tax cuts) can push the economy down the curve, reducing unemployment but increasing inflation.
  3. Central banks aim for a balance where inflation stays near the target (e.g., 2%) and unemployment is close to the natural rate.

📝 Examination Tips

When answering exam questions about the Phillips Curve:

  • Define the curve and show the basic inverse relationship.
  • Explain the role of expectations and how the curve shifts.
  • Use examples (e.g., 1970s stagflation) to illustrate real‑world relevance.
  • Discuss policy implications and the trade‑off between inflation and unemployment.
  • Remember to label your equations and use LaTeX notation for clarity.

Good luck, and keep thinking of the factory line analogy to remember the key points!