WHAT IS SUPPLY?
Supply is the amount of something, such as a product or service, that a market has available.
RELATIONS WITH MACROECONOMICS AND DEMAND
Demand and supply have also been generalized to explain macroeconomic variables in a market economy , including the quantity of total output and the general price level .
The Aggregate Demand-Aggregate Supply model may be the most direct application of supply and demand to macroeconomics, but other macroeconomic models also use supply and demand.
Compared to microeconomic uses of demand and supply, different (and more controversial) theoretical considerations apply to such macroeconomic counterparts as aggregate demand and aggregate supply .
Demand and supply may also be used in macroeconomic theory to relate money supply to demand and interest rates .