Transcript Supply

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THE
ECONOMIC
WAY OF
THINKING
What is Supply?
Where demand addresses the buying side of the
market, SUPPLY addresses the selling side
 Supply is how much of a good or service firms
produce or sell
 Law of Supply: the higher the price of a good,
the larger the quantity firms want to produce
 The amount a firm produces depends on various
factors
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The technological know-how concerning production of
the good, the cost and productivity of inputs required
for production, expectations, employee-management
relations, the goals of firms’ owners, the presence of
any government taxes or subsidies, etc…
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What is a Supply Curve?
The supply curve shows the influence of price on
a quantity supplied (other factors held constant)
 In the supply and demand graph, the supply
curve slopes upward.
 Why up? The per-unit opportunity costs rise
when more units are produced, so a higher price
is necessary for more output.

Prices are graphed on the Y-axis
 Units demanded (quantity) are graphed on the X-axis
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For each possible price on the Y-axis, the supply
curve identifies the sum of the quantities offered
for sale by firms
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Supply Curve
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What Does This Supply
Curve Show?
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When all else is held constant, it shows that at a
price of 20 pence per unit, the quantity supplied
will be 100
When all else constant, it shows that at a price of
50 pence per unit, the quantity supplied will be
400
The supply curve summarizes the effect of price
on the quantity that firms produce and sell
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What Changes Supply?
The supply curve shows the influence of price on
a quantity supplied, when other factors are held
constant. When any other factors change, the
entire supply curve shifts.
 (1) Technology: the state of technological
knowledge, how goods can be manufactured
 (2) Conditions of supply input
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Labor
Energy
(3) Other factors
Government - when it comes to health care
 Weather - when it comes to agriculture
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These Same Reasons
Shift the Supply Curve
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Change in Technology
Gutenburg invents the printing press in 1436
 Supply curve for book production shifts outwards,
reflecting an increase in the supply of books
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Change in Labor
General Motors lays off 47,000 employees in 2009
 Supply curve for GM car production shifts inwards,
reflecting a decrease in the supply of GM cars
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Change in Energy
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Petroleum cost more then $100/barrel summer 2008
Change in Weather
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Drought shrivels up wheat farms in China Feb 2009
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Shifts in Supply Curve
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Check out
http://www.bized.co.uk/learn/economics/markets/mechanis
m/interactive/part2.htm
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