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Supply shock
Supply shock – definition
A supply shock is a sudden and unexpected change in a cost variable, such as oil prices, commodity prices or wages. Shocks may be ‘negative’ or ‘positive’. Supply shocks may wear their way out the economic system quickly, leading to a one-off effect, or they may create an extended period of turbulence. For example, the oil shocks of the 1970s were so significant that their effects were extreme and long lasting.
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Graphically, it is common to show a negative supply shock with a leftward shift in the aggregate supply curve. In this case, the shock would trigger cost-plus inflation while at the same time causing a fall in real national income – a combination of effects referred to as ‘stag-flation’.