Foundationsmicroeconomics
Price Floors: When Governments Hold Prices Above Equilibrium
Overview
A price floor is a legal minimum price -- sellers may charge more but not less. When set above the equilibrium price (binding), it creates a persistent surplus: quantity supplied exceeds quantity demanded at the floored price. This lesson explains binding vs. non-binding floors, why the surplus does not self-correct, and applies the model to the two great real-world examples: minimum-wage laws in labor markets and agricultural price supports, where governments often buy up the surplus themselves.
Learning objectives
- Define a price floor and distinguish binding from non-binding floors.
- Explain why a binding floor creates a persistent surplus.
- Apply the floor model to minimum-wage laws.
- Apply the floor model to agricultural price supports and government purchases.
What a price floor is
A price floor sets the lowest legal price -- the minimum wage floors the price of labor, and farm programs floor crop prices. Like ceilings, floors only matter when binding: set above the equilibrium price, so the market wants to trade below it but cannot. A floor set below equilibrium is non-binding and changes nothing. The binding test is the mirror image of ceilings: floor above equilibrium = binding (surplus follows).
Floor above equilibrium = binding (surplus follows). Floor below equilibrium = non-binding (no effect).
Why a surplus results -- and persists
At the floored price, the high price encourages more selling (movement up the supply curve) while discouraging buying (movement up the demand curve): quantity supplied exceeds quantity demanded. Normally a surplus would push price down until balance returned -- but the price cut is illegal, so adjustment is blocked. The surplus persists: unsold goods pile up, or in labor markets, willing workers cannot find jobs at the going wage.
Minimum wage as a price floor
In a labor market, the wage is the price and workers are the suppliers. A minimum wage above the equilibrium wage for low-skilled labor creates a surplus of workers -- unemployment: more people seek jobs at that wage than employers will hire. Employers may also cut hours, automate, or hire more selectively. The policy's intent -- raising living standards -- is sympathetic, and workers who keep jobs earn more; but the model predicts fewer jobs and longer job searches, with the burden falling hardest on the least-skilled workers the policy aims to help. Empirical effects vary with how far above equilibrium the floor is set.
A floor just above equilibrium causes a small surplus; a floor far above causes a large one. This is why modest minimum wages show small employment effects in studies while large ones are riskier.
Agricultural price supports
Governments have long floored crop prices above equilibrium to support farm incomes. The surplus -- more wheat grown than buyers want at the floor price -- must go somewhere, so governments typically buy it up and store it, creating infamous 'grain mountains' and 'milk lakes,' or pay farmers to limit production (acreage set-asides). Taxpayers fund the purchases and consumers pay higher food prices: a transfer to farmers paid twice over. Modern farm policy has partly shifted to direct payments, which support incomes without distorting prices as much.
Winners, losers, and efficiency
Price floors redistribute: sellers who still sell gain (higher price), but buyers pay more and buy less, some sellers are rationed out entirely, and resources are wasted producing surplus nobody wants. Economists also note the irony that floors often help the relatively well-off within the protected group -- established farmers with big output, incumbent workers -- while harming outsiders: the unemployed, consumers, taxpayers. Like ceilings, floors pursue understandable goals through a mechanism that blocks market clearing.
Key points
- A price floor is a legal minimum; only floors above equilibrium (binding) have effects.
- A binding floor creates a persistent surplus because price cannot fall to clear the market.
- Minimum wage above equilibrium causes labor surplus -- unemployment -- especially for low-skilled workers.
- Farm price supports create surpluses governments must buy, store, or pay farmers not to produce.
- Floors redistribute toward incumbent sellers while costing buyers, taxpayers, and the excluded.
Common misconceptions
✓ Truth: Need does not determine hiring -- employers compare the wage with the value of the worker's output. When the floor exceeds what some workers' output is worth to employers, those jobs disappear or go unfilled. How large the effect is depends on how far above equilibrium the floor sits.
✓ Truth: Farmers are responding rationally to the guaranteed high price -- producing more is profitable. The surplus is the predictable result of the policy design, not farmer character. Blaming producers misses that the floor price is what incentivizes the overproduction.
✓ Truth: They help sellers who still manage to sell at the high price, but the surplus means some sellers cannot sell at all -- the unemployed worker, the farmer whose crop rots. Floors divide sellers into winners (those who sell) and losers (those rationed out).
Practice questions
Q1. A government sets a wheat price floor of $8 per bushel; equilibrium is $5. The result is:
- A binding floor creating a persistent surplus of wheat.
- A non-binding floor with no effect.
- A shortage of wheat.
- Lower wheat prices for consumers.
The floor is above equilibrium, so it binds: at $8, farmers supply more wheat than buyers demand -- a surplus. Price cannot legally fall to clear it, so the surplus persists until the government buys it, stores it, or pays farmers to cut production.
Q2. In the price-floor model of the labor market, a minimum wage set above equilibrium causes:
- A shortage of workers.
- A surplus of labor -- unemployment -- as more seek work than employers hire.
- Higher employment with no side effects.
- A leftward shift of the labor supply curve.
The wage floor is a price floor on labor: at the above-equilibrium wage, quantity of labor supplied (job seekers) exceeds quantity demanded (jobs offered). The gap is unemployment. Note this is a movement along the curves, not a shift.
Q3. Which group is typically HURT by a binding agricultural price floor?
- Large farmers who sell their full crop at the floor price.
- Consumers, who pay higher food prices, and taxpayers, who fund surplus purchases.
- Government storage agencies, which gain revenue.
- Farm equipment sellers, who face higher demand.
Binding floors raise food prices for consumers and force governments (taxpayers) to buy or manage the surplus. Large farmers who sell gain; but consumers, taxpayers, and farmers rationed out of sales bear the costs.
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Frequently asked questions
What is the difference between a binding and a non-binding price floor?
A binding floor is set above the equilibrium price, constraining the market and creating a surplus. A non-binding floor sits below equilibrium, where the market price already exceeds it, so nothing changes. Only binding floors have economic effects.
Why does a minimum wage cause unemployment in the model?
At the above-equilibrium wage, more workers offer their labor (movement up the supply curve) while employers hire fewer (movement up the demand-for-labor curve). Quantity of labor supplied exceeds quantity demanded -- a surplus of workers, i.e., unemployment among those seeking work at that wage.
What do governments do with farm surpluses from price supports?
Historically they bought and stored the surplus (creating stockpiles), gave it away as food aid, or paid farmers to idle land and produce less. Each option costs taxpayers; that is why many countries moved toward direct income payments that do not distort market prices.
Can a price floor ever be good policy?
It can achieve its distributional goal -- higher incomes for those who keep selling -- when set carefully. But economists note cheaper alternatives: wage subsidies (like earned-income tax credits) raise low incomes without destroying jobs, and direct farm payments support farmers without creating surpluses.