ForecastingStocks

Beneath every macro variable sits the most fundamental idea in economics: supply and demand. Prices — of goods, of labour, of money itself — are set by the balance between how much of something is available and how much people want it.

The basic mechanic

When demand exceeds supply, prices rise. Buyers compete for limited goods.
When supply exceeds demand, prices fall. Sellers compete for scarce buyers.
Markets tend toward an equilibrium price where the two balance.

This simple rule explains an enormous amount, from the price of coffee to the inflation rate to the level of interest rates (the "price" of money, set by the supply of credit versus the demand to borrow).

Why it matters to investors

Almost every market story is a supply-and-demand story:

An oil supply shock (a war, an OPEC cut) raises fuel prices, feeding cost-push inflation worldwide.
A bumper Brazilian harvest increases the supply of soy, pressuring its price lower.
Strong demand for a stock (more buyers than sellers) pushes its price up regardless of the company's fundamentals on that day.

Shocks and shifts

The economy is constantly hit by shocks that shift supply or demand — a pandemic, a drought, a stimulus cheque, a new technology. When you read that an event is "inflationary" or "deflationary", you are really being told whether it shifts the balance toward scarcity or abundance. Train yourself to ask, of any news: does this add to supply, or to demand? The answer usually tells you which way prices should move.