Subsidy — Government Subsidy Effect

What this diagram shows

This diagram illustrates how government subsidies affect market outcomes by shifting the supply curve downward and to the right. A subsidy is a payment from the government to producers, effectively reducing their production costs and encouraging increased output. The diagram shows how this intervention leads to a lower market price for consumers, higher quantity produced and consumed, and demonstrates the total cost to the government. This is a crucial concept for understanding how governments can correct market failures and achieve policy objectives.

Key points

• Supply curve shifts downward/rightward by the exact amount of the per-unit subsidy
• Market price falls from P1 to P2, benefiting consumers through lower prices
• Quantity increases from Q1 to Q2, showing increased market activity
• Total government expenditure equals the subsidy per unit multiplied by the new quantity (shown as shaded rectangle)
• Producers receive P3 per unit (P2 + subsidy) while consumers pay P2, creating a price wedge

Exam board notes

All major exam boards treat this diagram identically, requiring students to show the supply curve shift, price and quantity changes, and government expenditure calculation. Some boards may emphasise different policy contexts in their questions.