Excel Exercise - Pet Food Scenario
Demand Function Supply Function
QD = 200 ‐ 38.18PO + 8.35PS ‐ 2Pc + 10Inc + 0.8TS + 0.5M21 QS = ‐100 + 22.93PO ‐ 5PPI ‐ 10PS + 8Temp + 1Sup
Initial demand conditions Initial supply conditions
PO Price of syrah PO Price of syrah
PS Price of Substitutes: $18 PPI PPI: 111
PC Price of Cheese: $15 PS Price of Substitutes: $18
Inc Income: $53,000 Temp Temperature: 60
TS Trade Shows/Competitions: 3 Sup Number of Suppliers: 8,000
M21 Millennials = 45 million
Reference Table
Variable Coefficient values units total Variable Coefficient values units total
intercept 200 200 intercept ‐100 ‐100
PO ‐38.18 ??? #VALUE! PO 22.93 ??? #VALUE!
PS 8.35 18 $ 150.3 PPI ‐5 111 index ‐555
Pc ‐2 15 $ ‐30 PS ‐10 18 $ ‐180
Inc 10 53 thousands 530 Temp 8 60 degrees 480
Ts 0.8 3 2.4 Sup 1 8 thousands 8
M21 0.5 45 millions 22.5 Quantity Supplied #VALUE! millions of bottles
Quantity Demanded #VALUE! millions of bottles
Working Table
Variable Coefficient values units total Variable Coefficient values units total
intercept 200 200 intercept ‐100 ‐100
PO ‐38.18 21 ‐801.78 PO 22.93 21 481.53
PS 8.35 18 $ 150.3 PPI ‐5 123.222 index ‐616.11
Pc ‐2 15 $ ‐30 PS ‐10 18 $ ‐180
Inc 10 53 thousands 530 Temp 8 60 degrees 480
Ts 0.8 3 2.4 Sup 1 8 thousands 8
M21 0.5 45 millions 22.5 Quantity Supplied 73.42 millions of bottles
Quantity Demanded 73.42 millions of bottles
1. When the price of Syrah increases by $1, what is the effect on quantity demanded and quantity supplied?
Quantity demanded will fall by 38.18 million bottles when the price of Syrah rises by $1.
Quantity supplied will rise by 22.93 million bottles when the price of Syrah rises by $1.
2. How much does a $1 decrease in the price of substitute bottles of wine shift the demand and supply curves?
Demand will fall by 8.35 million bottles when the price of a substitute wine falls by $1.
Supply will rise by 10 million bottles when the price of a substitutes wine falls by $1.
3. Suppose the price of Syrah is currently $22 per bottle. How many bottles will be demanded and supplied monthly?
Price QD QS
22 35.24 157.46
quantity is in millions of bottles
4. If the market price of Syrah falls to $16 per bottle, how many bottles will be demanded and supplied monthly?
Price QD QS
16 264.32 19.88
quantity is in millions of bottles
5. Trying prices in $1 increments between $16 and $22, at what price and quantity does the market equilibrium occur?
Price QD QS
16 264.32 19.88
17 226.14 42.81
18 187.96 65.74
19 149.78 88.67
20 111.6 111.6 Market Equilibrium
21 73.42 134.53
22 35.24 157.46
quantity is in millions of bottles
6. Suppose the costs of production increase to 123.222. If the price of wine stays at $20 per bottle, what will be supplied in the market and will this create a shortage?
At a price of $20 and a PPI of 123.222, the quantity supplied in the market is 50.49 millions of bottles and the quantity demanded is 111.6 millions of bottles.
This causes a shortage of 61.11 million bottles.
7. With the increase in production costs to 123.222, at what price will the market be in equilibrium again? What will be demanded and supplied at this price?
When the production costs rise to 123.222, the new market equilibrium price is $21 and 73.42 million bottles will be bought and sold each month.