Transcript Unit 3_Economic Analysis_Cost
Unit 3 (cont.): Economic Analysis— Cost-Benefit Analysis 2
Some Key Terms
Initial (first) cost
A one-time investment cost incurred at the beginning of the life of a project (e.g. construction cost of a new road or school).
Recurring costs
Beyond the initial cost, many projects require the use of resources on a continual basis during their useful life time, e.g. annual costs on Operation and Maintenance (O&M) Recurring costs can be in the form of
Series
or
Non-uniform Series Uniform
Some Key Terms
Salvage value
Value of remaining assets of a project at the end of its useful life It represents a surplus of resources allocated to the project Because it is already included in the cost estimates, “Salvage value” should always be deducted from “Costs” during CBA calculations
What is Net Present Value (NPV)?
Formula for Calculating NPV
Generic formula: NPV = PVB – PVC
Benefits and costs have to be discounted
Benefits and costs may occur as initial values, uniform annual values, non uniform series, end-of-period values or any combination
Formula for Calculating NPV
Interpretation: Single Alternative
If NPV > 0, the proposed project is economically viable (efficient);
If NPV = 0, the benefits are just enough to offset costs; consider other criteria
If NPV < 0, the proposed project does not make economic sense (inefficient), reject it
Formula for Calculating NPV
Interpretation: Two or More Alternatives
All alternatives with NPV > 0 are economically viable (efficient)
Out of these, select alternative with the highest NPV
Formula for Calculating NPV Generic formula:
Let Bt = benefit in year t Ct = cost in year t r = discount rate; t = year 0, 1, 3, ….., n
Formula for Calculating NPV
Generic formula:
NPV
t n
0
B t
( 1
r
)
t
t n
0
C t
( 1
r
)
t
OR
NPV
t n
0
B t
C t
( 1
r
)
t
Example 1
As a planner working with a district assembly (DA) you have been tasked to evaluate the viability of a proposed economic development programme. The forecasted social costs and benefits of the programme for the next 8 years are shown in the table below.
Year 7 8 0 1 2 3 4 5 6
Cost (in $ million) 4.5
4.5
48.0
8.5
8.5
12.0
4.5
Benefits (in $ million) 20 20 12 12 12 12 20 20
Example 1 (cont.)
(i) Using a discount rate of 8% calculate the net present value of the programme and interpret your result.
(ii) Based on the result you obtain in (i) determine whether or not the proposed strategy is viable.
(iii) What should be the decision of the DA regarding the proposal?
Solution
(i) NPV:
t 0 1 2
Ct (in $ million) Bt (in $ million) 48.0
12 12 Bt – Ct -48.0
12 12 Discounted (Bt – Ct) -48.0 11.1 10.3
3
8.5
12 3.5
2.8
4
8.5
12 3.5
2.8
5
12.0
20 8 5.4
6
4.5
20
7
4.5
20
8
4.5
20 15.5 15.5 15.5
9.8
9.0
8.4
NPV
t
8 0
B t
C t
( 1 0 .
08 )
t
$ 11 .
6
mil
.
Solution
Interpretation of result
Discounted value of social benefits of the proposed programme exceeds discounted value of its social costs by $11.6 million.
(ii) Viability of proposed progrmme:
The proposed programme is economically viable because its NPV is greater than zero
Solution
(iii) What the DA should do:
The proposed programme should be adopted because its NPV shows it is economically viable
Formula for Calculating NPV
When annual benefits and costs occur as “uniform series” with or without initial values:
Let B0 = benefit in year 0 AB = uniform annual benefit C0 = cost in year 0 AC = uniform annual cost r = discount rate; t = total number of years
Formula for Calculating NPV
When annual benefits and costs occur as “uniform series” with or without initial values:
NPV
B
0
AB
1
r
1
r
t r
t
1
C
0
AC
1
r
1
r
t r
t
1
OR
NPV
B
0
C
0
AB
AC
1
r
1
r
t r
t
1
Example 2
GoG is considering a proposal to construct a new bypass around city “A”. The proposal will involve an initial cost of $60 million (for construction) and $2.25 million annually for maintenance. The bypass has an estimated life of 20 years during which it is expected to yield social benefits of $9.75 million every year.
(i) Using a discount rate of 8%, calculate the net present value of the proposed project (ii) Interpret your answer for (i) (iii) Based on your results make a recommendation to GoG
Solution
(i) NPV: C 0 =$60 million; AC = $2.25 million; B 0 = 0; AB = $9.75 million; t = 20; r = 8%
NPV
B
0
C
0
AB
AC
1
r
1
r
t r
t
1
NPV
$ 0 $ 60
mil
$ 9 .
75 $ 2 .
25 1 0 .
08 0 1 .
08 20 0 .
08 1 20 $ 13 .
64
mil
Solution
(ii) Interpretation: Discounted (present) value of the social benefits of proposed project exceeds discounted (present) value of its social costs by $13.64 million (iii) Recommendation: Since NPV > 0, the proposal is economically viable (efficient) and is recommended for approval by GoG.
Trial Question 1
A proposal for providing electricity to a small remote town for 40 years is being considered by government. The investment costs, operation and maintenance (O&M) costs, benefits and disbenefits of the proposal are as summarized in the table below. Using a discount rate of 6%, calculate the net present value of the proposal and determine whether it is economically justifiable
Description
Annual benefits, $/year Present value of all disbenefits, $ Investment (initial) costs, $ O&M costs, $/year Project life, years
Estimates
72,500,000 76,600,000 300,500,000 49,000,000 40
Trial Question 2
GoG is considering two alternative proposals to improve road safety and reduce traffic congestion in city “A”: (a) constructing a new bypass or (b) upgrading existing roadways. The initial cost of GHC60 million and annual maintenance costs of GHC2.25 million. It is expected to yield benefits of GHC9.75 million per year. The Upgrading Proposal Bypass Proposal will have an has an initial cost of GHC7 million, annual maintenance costs of GHC262,500 and annual social benefits of GHC1.14 million. Each project has a life of 30 years. The Bypass Proposal, which would have donor funding component, involves a discount rate of 8% while the Upgrading Proposal, to be funded wholly by government, has a discount rate of 4%.
i.
ii.
Calculate the net present value of each proposal and determine if it is economically viable Which of the two proposals is more economically justifiable.
Benefit-Cost Ratio (BCR)
Defined simply as:
BCR =
Discounted Benefits Discounted Costs
Benefit-Cost Ratio (BCR)
It gives indication of how much benefit will be produced for every GHC1 of cost incurred on a programme or project E.g. BCR of 1.5 means for every GHC1 of cost incurred, $1.5 worth of benefits will be produced BCR of 0.7 means for every GHC1 of cost incurred, GHC0.7 worth of benefits will be produced What about: BCR of 2.0? BCR of 1.0?
Benefit-Cost Ratio (BCR)
Rules: If CBR > 1, the project is economically viable (efficient) because its social benefits exceed its social costs; accept it on the basis of the efficiency If CBR = 1, the social benefits of the project are just enough to offset its social costs; other criteria need to be considered in making a decision If CBR < 1, the project does not make economic sense (inefficient) because its social costs exceed its social benefits; reject it on the basis of efficiency
Formula for Calculating BCR
Generic formula:
BCR
t n
0
t n
0
B t
( 1
r
)
t C t
( 1
r
)
t
Example 3
As a planner working with a district assembly (DA) you have been tasked to evaluate the viability of a proposed economic development programme. The forecasted social costs and benefits of the programme for the next 8 years are shown in the table below.
Year 7 8 0 1 2 3 4 5 6
Cost (in $ million) 4.5
4.5
48.0
8.5
8.5
12.0
4.5
Benefits (in $ million) 20 20 12 12 12 12 20 20
Example 3 (cont.)
(i) Using a discount rate of 8% calculate the BCR of the programme and interpret your result.
(ii) Based on the result you obtain in (i) determine whether or not the proposed strategy is viable.
(iii) What should be the decision of the DA regarding the proposal?
Solution
(i) BCR:
t 0
Ct (in $ million) 48.0
Discounted Ct 48.0
Bt (in $ million) Discounted Bt 0
1
12
2
12
3
8.5
4 5 6
8.5 12.0 4.5
7
4.5
8
4.5
12 12 20 20 20 20 ∑
BCR
t n
0
t n
0
B t
( 1
r
)
t C t
( 1
r
)
t
Solution
Formula for Calculating BCR
When annual benefits and costs occur as “uniform series” with or without initial values:
BCR
B
0
AB
( 1
r
( 1
r
)
t
r
1 )
t
C
0
AC
( 1
r
( 1
r
)
t
r
1 )
t
Example 4
GoG is considering a proposal to construct a new bypass around city “A”. The proposal will involve an initial cost of $60 million (for construction) and $2.25 million annually for maintenance. The bypass has an estimated life of 20 years during which it is expected to yield social benefits of $9.75 million every year.
(i) Using a discount rate of 8%, calculate the BCR of the proposed project (ii) Interpret your answer for (i) (iii) Based on your results make a recommendation to GoG