
206 Part III Investment risk and return
New risks put scenario planning in favour
FT
Who could have predicted the
horrific events of September 11,
2001? A 1999 US congressional
commission led by former sena-
tors Gary Hart and Warren
Rudman came close. It warned
that the US was ‘increasingly vul-
nerable to attack on our home-
land’ and that ‘rapid advances in
information and biotechnologies
will create new vulnerabilities’.
But perhaps more important
than the commission’s prophetic
messages was its approach.
Instead of forecasting a specific
future, it set out a collection of
possible attack scenarios. It then
evaluated national security by
analysing possible policies to pre-
pare for, or respond to them.
This approach – known as
scenario planning – has gained
renewed popularity among pub-
lic and private decision-makers.
In January this year, the New
England Journal of Medicine pub-
lished a scenario planning analysis
on whether US health workers or
the whole nation should be vacci-
nated against smallpox to counter
the threat of bio-terrorism. Presi-
dent George W. Bush decided to
inoculate 500,000 military person-
nel and 439,000 health workers.
Scenario planners face three
challenges. The first is construct-
ing meaningful scenarios. This
requires expert analysis of the
factors that affect the outcomes. A
second challenge is determining
the likelihoods of the scenarios.
Finally, planners must decide
on a good criterion for selecting
strategies. Most individuals and
institutions are risk-averse: they
value an uncertain reward at a
level significantly below the aver-
age level the reward in fact reach-
es. Strategies with higher average
pay-offs often entail greater risks.
Hence, scenario planning often
involves analysing the reward at
different levels of risk – much as
is done in financial planning.
What explains the recent inter-
est in scenario planning? For one
thing, we live in turbulent times.
Terrorism, political instability
and threats of war make scenar-
ios of extreme price fluctuations
in commodity and energy mar-
kets more likely. Severe acute res-
piratory syndrome, ‘mad cow
disease’ and foot-and-mouth dis-
ease have rekindled awareness of
the natural biological threats we
face. Accounting scandals force us
to second-guess what used to be
considered accurate information
about suppliers and customers. In
short, companies face far greater
risks than before. Indeed, when
Mattel used scenario planning to
formulate its 2002 strategy, it
considered scenarios with several
big customers (such as Kmart,
FAO and eToys) going bankrupt
and others (Wal-Mart) starting to
make their own toys.
Source: Awi Federgruen and Garrett Van Ryzin,
Financial Times, 19 August 2003, p. 11.
Sensitivity analysis, as applied in the above example, discloses that selling price and
variable costs are the two most critical variables in the investment decision. The deci-
sion-maker must then determine (subjectively or objectively) the probabilities of such
changes occurring, and whether he or she is prepared to accept the risks.
■ Scenario analysis
Sensitivity analysis considers the effects of changes in key variables only one at a time.
It does not ask the question: ‘How bad could the project look?’ Enthusiastic managers
can sometimes get carried away with the most likely outcomes and forget just what
might happen if critical assumptions – such as the state of the economy or competitors’
reactions – are unrealistic. Scenario analysis seeks to establish ‘worst’ and ‘best’ scenar-
ios, so that the whole range of possible outcomes can be considered. It encourages ‘con-
tingent thinking’, describing the future by a collection of possible eventualities.
Discount rate
The break-even annuity factor is £200,000/£76,000=2.63. Reference to the present value
annuity tables for four years shows that 2.63 corresponds to an IRR of 19 per cent. The error
in cost of capital calculation could be as much as nine percentage points before it affects the
decision advice.
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