Supply and demand (basics)

Why does the same toy cost $20 in November and $40 the week before Christmas? Why are fresh strawberries cheap in June and expensive in January? The answer is the same in every shop, every market, every country: SUPPLY and DEMAND. These two forces decide how high or low a price goes — and once you understand the simple rule, you can predict price changes almost like a scientist.

Supply — how much is available

SUPPLY is HOW MUCH of something is available to buy at a given moment. If a farm grows a huge crop of apples, the supply of apples is HIGH. If a storm wipes out half the crop, the supply is LOW. Supply changes because of the weather, factories, harvests, accidents, or how many workers are making the thing. Supply is about the SELLER side of the market.

• A bumper harvest of pumpkins — supply is HIGH.
• A frost destroys an orange crop — supply is LOW.
• A new factory doubles its sneaker output — supply is HIGH.
• A fishing boat breaks down for a week — supply is LOW.

Demand — how much people want

DEMAND is HOW MUCH people want to buy something at a given moment. If everyone in your neighborhood is talking about the same trading card, demand is HIGH. If a fashion is over and nobody cares any more, demand is LOW. Demand changes because of the season, fashion, news, ads, holidays, or weather. Demand is about the BUYER side of the market.

• Sleds in a snowstorm — demand is HIGH.
• Sunscreen in winter — demand is LOW.
• A new game everyone is talking about — demand is HIGH.
• Old phones that nobody wants any more — demand is LOW.

The big rule — what makes prices move

When SUPPLY is LOW and DEMAND is HIGH, prices go UP — there is not enough to go around, so sellers can charge more and buyers will still pay. When SUPPLY is HIGH and DEMAND is LOW, prices go DOWN — there is too much sitting on the shelf, so sellers cut the price to clear it out. That single rule explains almost every price change you will ever see.

Real-world examples

1. TOYS BEFORE CHRISTMAS — demand spikes in December. Supply cannot grow that fast, so prices RISE.
2. STRAWBERRIES IN WINTER — supply drops because they do not grow locally in cold weather. Prices RISE.
3. PUMPKINS IN NOVEMBER — Halloween is over, demand drops, supply is still big. Prices FALL.
4. BEACH UMBRELLAS IN OCTOBER — summer is over, demand drops, shops still have lots. Prices FALL.
5. CONCERT TICKETS FOR A FAMOUS BAND — only a few thousand seats (low supply), millions want them (high demand). Prices RISE.

Price as a balance — the market self-corrects

PRICE is the signal that brings supply and demand back into balance. If prices are too HIGH, fewer people buy and more sellers want to sell — so demand drops, supply piles up, and prices fall. If prices are too LOW, lots of people buy and fewer sellers bother to sell — so demand rises, supply runs out, and prices climb. The market keeps adjusting until supply and demand roughly match. That balance point is called the EQUILIBRIUM PRICE.