Weighing-Scale Approach to
Decision-Making
Cost-Benefit Analysis
Cost-benefit analysis (CBA) is
the weighing-scale approach to decision-making. All the plusses (cash-flows and
other intangible benefits) are put on one side of the balance and all the
minuses (the costs and disadvantages) are put on the other. Whichever weighs
the heavier wins.
Example of a Weighing-Scale
Approach:
A company that would like to
buy new software to improve its business might conduct a CBA to decide and make
up its mind.
On the minus (cost) side would
be:
- the price of the software,
- the cost of consultants to
install and implement the software, and
- the cost of training for the
users of the software.
However on the plus (benefits)
side would be:
- improved business processes
(leading to an annual cost decrease),
- due to better available
information, being able to take better decisions (leading to additional
cash-flows), and
- increased staff moral from
using the state of the art tools for running the business.
A frequently made mistake in
the CBA method is to use non-discounted amounts for calculating the costs and
benefits. A method like NPV or Economic Value Added or CFROI is strongly
recommended, because all of these account for the time value of money.
A frequent problem with CBA is
that typically the cost are tangible, hard and financial, while the benefits are
hard and tangible, but also soft and intangible. Caution should be taken here
against people who claim that "if you can't measure it does not exist / it has
no value". Especially in more strategic investments, frequently the intangible
benefits clearly outweigh the financial benefits
Cost-Benefit Analysis
Cost-benefit analysis is a term
that refers both to:
-
a formal discipline used to
help appraise, or assess, the case for a project or proposal, which itself
is a process known as project appraisal; and
-
an informal approach to
making decisions of any kind.
Under both definitions the
process involves, whether explicitly or implicitly, weighing the total expected
costs against the total expected benefits of one or more actions in order to
choose the best or most profitable option. The formal process is often referred
to as CBA, or Cost-Benefit analysis in the United States.
Closely related, but slightly
different, formal techniques include cost-effectiveness analysis and benefit
effectiveness analysis.
Theory of Cost Benefit
Analysis
Cost Benefit Analysis is an
economic tool to aid social decision-making, and is typically used by
governments to evaluate the desirability of a given intervention in markets. The
aim is to gauge the efficiency of the intervention relative to the status quo.
The costs and benefits of the impacts of an intervention are evaluated in terms
of the public's willingness to pay for them (benefits) or willingness to pay to
avoid them (costs). Inputs are typically measured in terms of opportunity costs
- the value in their best alternative use. The guiding principle is to list all
of the parties affected by an intervention, and place a monetary value of the
effect it has on their welfare as it would be valued by them.
The process involves monetary
value of initial and ongoing expenses vs. expected return. Constructing
plausible measures of the costs and benefits of specific actions is often very
difficult. In practice, analysts try to estimate costs and benefits either by
using survey methods or by drawing inferences from market behaviour. For
example, a product manager may compare manufacturing and marketing expenses to
projected sales for a proposed product, and only decide to produce it if he
expects the revenues to eventually recoup the costs. Cost-benefit analysis
attempts to put all relevant costs and benefits on a common temporal footing. A
discount rate is chosen, which is then used to compute all relevant future costs
and benefits in present-value terms. Most commonly, the discount rate used for
present-value calculations is an interest rate taken from financial markets
(R.H. Frank 2000). This can be very controversial - for example, a high discount
rate implies a very low value on the welfare of future generations, which may
have a huge impact on the desirability of interventions to help the environment,
and so on. Empirical studies have suggested that in reality, people's discount
rates do decline over time. Because CBA aims to measure the public's true
willingness to pay, this feature is typically built into studies.
During cost-benefit analysis,
monetary values may also be assigned to less tangible effects such as the
various risks which could contribute to partial or total project failure; loss
of reputation, market penetration, long-term enterprise strategy alignments,
etc. This is especially true when governments use the technique, for instance to
decide whether to introduce business regulation, build a new road or offer a new
drug on the state healthcare. In this case, a value must be put on human life or
the environment, often causing great controversy. The cost-benefit principle
says, for example, that we should install a guardrail on a dangerous stretch of
mountain road if the dollar cost of doing so is less than the implicit dollar
value of the injuries, deaths, and property damage thus prevented (R.H. Frank
2000).
Cost-benefit calculations
typically involve using time value of money formula. This is usually done by
converting the future expected streams of costs and benefits to a present value
amount.
Application of Cost Benefit
Analysis
Cost-benefit analysis is
mainly, but not exclusively, used to assess the value for money of very large
private and public sector projects. This is because such projects tend to
include costs and benefits that are less amenable to being expressed in
financial or monetary terms (e.g. environmental damage), as well as those that
can be expressed in monetary terms. Private sector organisations tend to make
much more use of other project appraisal techniques, such as rate of return,
where feasible.
The practice of cost-benefit
analysis differs between countries and between sectors (e.g. transport, health)
within countries. Some of the main differences include the types of impacts that
are included as costs and benefits within appraisals, the extent to which
impacts are expressed in monetary terms and differences in discount rate between
countries.
Cost Benefit Analysis in UK
Basic cost-benefit techniques
were applied to the development of the motorway network in the 1950s and 60s. An
early, and often quoted, more developed application of the technique was made to
London Underground's Victoria Line. Over the last 40 years, cost-benefit
techniques have gradually developed to the extent that substantial guidance now
exists on how transport projects should be appraised in the UK. The Department
for Transport (DfT) and its agencies have made extensive use of a number of key
cost-benefit indicators, including:
-
PVB (present value of
benefits);
-
PVC (present value of
costs);
-
NPV (PVB less PVC);
-
NPV/k (where k is the level
of funds available) and
-
BCR (benefit cost ratio).
In 1998 the New Approach to
Appraisal (NATA) was introduced by the then Department for Transport,
Environment and the Regions. This brought together cost-benefit results with
those from detailed environmental impact assessments and presented them in a
balanced way. NATA was first applied to national road schemes in the 1998 Roads
Review, but subsequently rolled out to all modes of transport. It is now a
cornerstone of transport appraisal in the UK and is maintained and developed by
the Department for Transport.
Cost Benefit Analysis in EU
The EU's 'Developing Harmonised
European Approaches for Transport Costing and Project Assessment' (HEATCO)
project, part of its Sixth Framework Programme, has reviewed transport appraisal
guidance across EU member states and found that significant differences exist
between countries. HEATCO's aim is to develop guidelines to harmonise transport
appraisal practice across the EU.
Cost Benefit Analysis in US
Much of the early development
work on cost-benefit analysis as a discipline was the result of problems faced
by the US Army Corps of Engineers in deciding how and where to build bridges in
supporting combat operations.
Cost-benefit analysis is now a
well established discipline in the US. California's Department of Transportation
(Caltrans) provide detailed guidance on how Cost-benefit analysis should be
applied to transport projects.
Evolutionary biology of Cost
Benefit Analysis
Cost-benefit analysis is used
in evolutionary biology to assess the fitness costs and benefits of traits. For
example, a behavioral ecologist may use the cost benefit approach to explain the
evolution of play behavior in young animals. Costs would include injury and
increased vulnerability of predation, while benefits may include improvement of
a certain skill important in future success. Deviation from predictions based on
the cost-benefit approach may highlight factors not considered by the
researcher.
Accuracy problems in Cost
Benefit Analysis
The accuracy of the outcome of
a cost-benefit analysis is dependent on how accurately costs and benefits have
been estimated. A peer-reviewed study of the accuracy of cost estimates in
transportation infrastructureplanning found that for rail projects actual costs
turned out to be on average 44.7 percent higher than estimated costs, and for
roads 20.4 percent higher (Flyvbjerg, Holm, and Buhl, 2002). For benefits,
another peer-reviewed study found that actual rail ridership was on average 51.4
percent lower than estimated ridership; for roads it was found that for half of
all projects estimated traffic was wrong by more than 20 percent (Flyvbjerg,
Holm, and Buhl, 2005). Comparative studies indicate that similar inaccuracies
apply to fields other than transportation. These studies indicate that the
outcomes of cost-benefit analyses should be treated with caution, because they
may be highly inaccurate. In fact, inaccurate cost-benefit analyses may be
argued to be a substantial risk in planning, because inaccuracies of the size
documented are likely to lead to inefficient decisions, as defined by Pareto and
Kaldor-Hicks efficiency ( Flyvbjerg, Bruzelius, and Rothengatter, 2003).
These outcomes (almost always
tending to underestimation, unless significant new approaches are overlooked)
are to be expected, since such estimates:
1. rely heavily on past like
projects (frequently differing markedly in function or size, and certainly in
the skill levels of the team members),
2. rely heavily on the
project's members to identify (remember from their collective past experiences)
the significant cost drivers,
3. rely on very crude
heuristics ('rules of thumb') to estimate the money cost of the intangible
elements, and
4. are unable to completely
dispel the usually (unconscious) biases of the team members (who often have a
vested interest in a decision to 'go ahead') and the natural psychological
tendency to "think positive" (whatever that involves).
Another challenge to
cost-benefit analysis comes from determining which costs should be included in
an analysis (the significant cost drivers). This is often controversial as
organizations or interest groups may feel that some costs should be included or
excluded from a study.
In the case of the Ford Pinto
(where, due to design flaws, the Pinto was liable to burst into flames in a
rear-impact collision), the Ford company's decision was not to issue a recall.
Ford's cost benefit analysis had estimated that: based on the number of cars in
use and the probable accident rate, deaths due to the design flaw would run
about $49.5 million (the amount Ford would pay out of court to settle wrongful
death lawsuits). This was estimated to be less than the cost of issuing a recall
($137.5 million). In the event, Ford overlooked (or considered insignificant)
the costs of the negative publicity so engendered, which turned out to be quite
significant (since it led to the recall anyways and to measurable losses in
sales).
Specifically in the field of
Health Economics, cost-benefit analysis is viewed as an inadequate measure by
extra-welfarists, as willingness-to-pay methods of determining the value of
human life are subject to bias according to income inequity. This is due to the
inherent nature of "ability to pay," which weighs heavily in the
willingness-to-pay question (i.e. one's willingness-to-pay is constrained by
one's ability-to-pay). For this reason, extra-welfaristscost-utility analysis
and the QALY to analyze the effects of health policies. support use of
Sources and further reading
about Cost Benefit Analysis
-
Sukhamoy Chakravarty
(1987). "cost-benefit analysis," The New Palgrave: A Dictionary of
Economics, v. 1, pp. 687-90.
-
Bent Flyvbjerg, Nils
Bruzelius, and Werner Rothengatter, Megaprojects and Risk: An Anatomy of
Ambition (Cambridge University Press, 2003).
-
Bent Flyvbjerg, Mette K.
Skamris Holm, and S�ren L. Buhl, "Underestimating Costs in Public Works
Projects: Error or Lie?" Journal of the American Planning Association, vol.
68, no. 3, Summer 2002, pp. 279-295.
-
Bent Flyvbjerg, Mette K.
Skamris Holm, and S�ren L. Buhl, "How (In)accurate Are Demand Forecasts in
Public Works Projects? The Case of Transportation." Journal of the American
Planning Association, vol. 71, no. 2, Spring 2005, pp. 131-146.
-
Tevfik F. Nas, Cost-Benefit
Analysis: Theory and Application (Thousand Oaks, Ca.: Sage, 1996).
-
Folland, Sherman, Allen C.
Goodman and Miron Stano. The Economics of Heath and Health Care. Fifth ed.
Pearson Prentice Hall: New Jersey, 2007. pg 83, 84.
-
Ascott, Elizabeth. 2006.
Benefit Cost Analysis of Wonderworld Drive Overpass in San Marcos, Texas.
Applied Research Project. Texas State University.
http://ecommons.txstate.edu/arp/104/
References
http://en.wikipedia.org/wiki/Cost-benefit_analysis
http://www.valuebasedmanagement.net/methods_cost-benefit_analysis.html |