$\ \frac{\Delta Total\ Cost\ }{\Delta Quantity}$  

 $\ \frac{\Delta Variable\ Cost\ }{\Delta Quantity}$  

 $\frac{\text{d}P}{\text{d}Q}\ of\ Total\ Cost$  

 $\frac{Total\ Cost}{Quantity}$  

ATC = MC

MC = ATC

MC = AR

ATC = MR

P < ATC

AVC < P < ATC

P = ATC

P < AVC

An innovation that decreases MC

A decreased demand for the product

An increase in an input cost

More firms enter the industry

Create inflation

Counter inflation

Decrease unemployement

Increase GDP

Minimum wages

Employment contracts

Trade unions

Government spending

Increasing aggregate supply

Increasing aggregate demand

Decreasing aggregate demand

Decreasing aggregate supply

Nobody knows....

Keynes believed it was a failure of the free market; Friedman a failure of the Federal Reserve

Keynes believed it was a failure of the Federal Reserve; Friedman a failure of the free market

Keynes believed it was a failure of government intervention; Friedman a failure of foreign policy