Price changes · ⁨价格变化⁩

When the whole market moves

• A heatwave empties the shops of ice cream; a health scare empties them of a food. Prices jump or slump.
• These are shifts 移动 in demand 需求 or supply 供给 — and they move the equilibrium 均衡 to a new place.

A demand shift

• More demand (right shift) → at the old price there's a shortage 短缺 → price rises, quantity rises.
• Less demand (left shift) → price falls, quantity falls.

A rise in demand shifts the curve right: the new equilibrium has a higher price and quantity.

A supply shift

• More supply (right shift) → price falls, quantity rises.
• Less supply (left shift) → price rises, quantity falls.

A rightward shift of supply lowers the price and raises the quantity; a leftward shift does the reverse

A method that always works

• 1. Decide which curve moves and which way.
• 2. Mark the new crossing point.
• 3. Read off the new price and quantity.

You've got it