Question:
ABC company has conducted a U.S market survey for their most popular brand of contact lenses, and obtained the following information. What is the elasticity of demand?
|
Year
|
Population
|
Price
|
Average Income
|
Eyeglass
|
Population
|
Number of
|
Quantity Demanded
|
|
(millions)
|
(adjusted
|
(adj. for inflation)
|
Price
|
Vision
|
Optometrists
|
(millions of pairs)
|
|
|
for inflation)
|
|
Index
|
Index
|
(per 100,000
|
|
|
|
|
|
|
|
population)
|
|
|
|
|
|
|
|
|
|
|
2004
|
30
|
10.00
|
$33k
|
100
|
Fair
|
6
|
3.15
|
|
2005
|
30
|
10.30
|
$34k
|
100
|
Good
|
7
|
3.25
|
|
2006
|
31
|
11.00
|
$35k
|
100
|
Good
|
7
|
3.4
|
|
2007
|
31
|
11.25
|
$35k
|
100
|
Good
|
7
|
3.3
|
|
2008
|
31
|
11.40
|
$36k
|
100
|
Good
|
8
|
3.55
|