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Evaluating Risk in Property Feasibility Studies A component of the research project into: The Functional Performance of Commercial Buildings 19 June, 2003 CRC CI Project 11

Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

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Page 1: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Evaluating Risk in Property Feasibility Studies

A component of the research project into:

The Functional Performance of Commercial Buildings

19 June, 2003 CRC CI Project 11

Page 2: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Evaluating RISK

All property projects are risky

To maximise profits, risk must be:IdentifiedQuantifiedManaged

Page 3: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Today’s Program

2.00 – 3.30 pm: Cash Flow model accuracyShort tutorialKey variables and the marketBasic risk measurement

3.30 – 3.45 pm: Tea break

3.45 – 5.00 pm: Scenario analysisShort tutorialSimulation exerciseTriple bottom line assessment

Page 4: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Investment Worth

Standard Measure of Rate of Return:

= END PERIOD – BEGINNING PERIOD + CASH FLOW x 100BEGINNING PERIOD

This is the approach used for property investment and development studies but sometimes we simplify the exercise.

1. Simple (Static) Exercise:Calculation of worth or profit in a single time period - this is the yield or direct capitalisation approach

2. Full (Cash flow) Exercise:Examining the cash flow over time – this is the Discounted cash flow (DCF) approach.

Page 5: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Cash Flow Models

These models:

show the anticipated cash flow ( both income stream and capital change) over a specified time periodare used to determine either

1. Present Value ( or net present value)i.e. the worth today

2. Internal Rate of Returni.e. the total annual return achieved on funds during the time period specified.

Page 6: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Cash Flow Spreadsheets

STRUCTURE: OUTCOME – NPV (or PV)Known:Net income estimate over timeFuture selling price estimateRequired total rate of return (discount rate)

Period 0 Period 1 Period 2 Period 3 Period … Period n PURCHASE

SALE

CASH FLOW

Compute: Net Present Value (Present Value)

N.B. May include or exclude a present value figure

Assumptions: Outcome NPV (or PV)1. Length of study 2. Time interval 3. All net income figures over time 4. Any capital items (input or expense)5. All sale figures6. Required rate of return (target rate)

GROSS INCOMEOPERATING EXPENSESNET INCOMECAPITAL EXPENDITURE

Page 7: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Cash Flow SpreadsheetsSTRUCTURE: OUTCOME - IRRKnown:Present value (purchase price or value)Net income estimate over timeFuture selling price estimate

Compute IRRIRR is the rate of return that makes the future cash flows equal to the present cash flow.

Assumptions: Outcome NPV (or PV)1. Length of study (3, 5 or 10 years…)2. Time interval (monthly, annual…)3. All purchase/present value figures, including costs.4. Net income figures over time including starting and finishing dates and escalation rates of

income and expense5. Any capital expenditure or inputs.6. All sale/terminal value figures, including costs.

Period 0 Period 1 Period 2 Period 3 Period … Period n PURCHASE

SALE

CASH FLOW

GROSS INCOMEOPERATING EXPENSESNET INCOMECAPITAL EXPENDITURE

Page 8: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Tutorial - Incorporating Loan Finance in a DCF exercise

Study the layout of this Property Investment case flow study and insert the additional headings required in the left-hand column to assess the Internal Rate of Return on Equity.

Will the IRR on Equity be greater or lesser than the IRR on Total Capital (10.51%)?

Page 9: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Diagram for NPV computationYear is the time intervalt1…tn is the length of studytn+1 is the extra year

NPV = (disc rate, CF2…CFn) + CF1

Sale Price = Net Income tn+1Terminal Cap Rate

Known inputs

Key variables

Assumptions

OperatingExpenses

HistoricalOPEX

VacancyAllowance

Net LettableArea

Cash Flow

CapitalExpenditure

NetIncome

GrossIncome

TerminalCap Rate

DiscountRate

RentalGrowthRates

Sale Price

t n + 1

Sale Costs

CurrentMarket Value

PurchaseCosts

t =1...n

NPV(PV)

t = n

CPI Forecast

OPEXBenchmarks

Market RentLevels

RentSchedules

t1 ... tn

t1 ... tn

t1 ... tn

Page 10: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Diagram for IRR computationYear is the time intervalt1…tn is the length of studytn+1 is the extra year

Sale Price = Net Income tn+1Terminal Cap Rate

IRR = (CF1…CFn)

OperatingExpenses

HistoricalOPEX

VacancyAllowance

Net LettableArea

CapitalExpenditure

NetIncome

GrossIncome

TerminalCap Rate

RentalGrowthRates

Sale Price

t n + 1

Sale Costs

t =1...n

t = n

CPI Forecast

OPEXBenchmarks

Market RentLevels

RentSchedules

t1 ... tn

t1 ... tn

t1 ... tn

Cash Flow

PurchaseCostsIRR

PurchasePrice

Known inputs

Key variables

Assumptions

Page 11: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Rental Growth Rates

Space perWorker

Rent [R]

o

EquilibriumRent [R*]

s

SpaceDemand [OC*]

Employment [E]

s

s

o

Net SpaceAbsorption [AB]

s

s

DesiredCompletions [C*]

o

OccupiedSpace [OC]

s

o

Vacancy [V]

oo

o

Stock [S]

s o

Demolition ¬Α!

o

Completions [C]

o

s

s

+

+

+ -

Negative Feedback: a discrepancy induces corrective action to return the system to a target state (Equilibrium Rent).

Positive Feedback: growth leads to faster growth or decrease accelerates a collapse (space per worker).

Page 12: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

System Dynamics Concepts

System Dynamics theories, as developed by Forrester (1961) and enhanced by Coyle (1977), offer the opportunity to model complex interrelationships and to observe their dynamic behavior over time.

The use of dynamic models:

Provide more reliable forecasts of short to mid-term trends than statistical models – time-series models and regression models.

Provide a means of understanding the causes of industry behaviour.

Allow the determination of reasonable scenarios as inputs to decisions and policies.

Page 13: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Professional – DCF Market Rent Forecasts

Comparison - DCF - Forecasts Market Rent Growth

-8.00%

-6.00%

-4.00%

-2.00%

0.00%

2.00%

4.00%

6.00%

8.00%

10.00%

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Year

% C

hang

e

Company A Company B Company C Company D Company E Economists

Page 14: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Brisbane CBD – Historical % Change – Face Rents

Brisbane CBD - Historical % Change - Office Face Rents

-40.00%

-30.00%

-20.00%

-10.00%

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

Year

% C

hang

e

Prime SecondarySource - BIS

Page 15: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Professional – Inflation Forecasts

Comparison - ForecastsCPI Growth

0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

6.00%

7.00%

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Year

% C

hang

e

Company A Company B Company C Company D Company E Economists

Page 16: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Brisbane – Historical Inflation - % Change

Consumer Price Index - All Groups - Brisbane - Historical Movement

0.00%2.50%5.00%7.50%

10.00%12.50%15.00%17.50%20.00%22.50%25.00%

1949

-50

1952

-53

1955

-56

1958

-59

1961

-62

1964

-65

1967

-68

1970

-71

1973

-74

1976

-77

1979

-80

1982

-83

1985

-86

1988

-89

1991

-92

1994

-95

1997

-98

2000

-01

Financial Year

% C

hang

e

Source - ABS

Page 17: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

DCF Results Comparison – Alternate Rent & CPI Forecasts

DCF Results Comparison - Alternate Rent & CPI Forecasts

$107

,500

,000

$108

,000

,000

$108

,500

,000

$105

,000

,000

$102

,000

,000

$105

,500

,000

$50,000,000

$60,000,000

$70,000,000

$80,000,000

$90,000,000

$100,000,000

$110,000,000

$120,000,000

Company A Company B Company C Company D Company E Economists

Forecast Source

$

Page 18: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Economic Factors & Property Variables

Historical Relativity - Property and Economic Factors

0

50

100

150

200

250

1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Year

Inde

x

Building Net Income Effective Rents Inflation Vacancies

Construction Employment Gross State Product

Source: ABS, BIS Shrapnel & PCA

Page 19: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Correlations – Economic Factors & Property Variables

10.750.42-0.360.910.030.83GSP

1.000.66-0.350.81-0.160.76Employment

1.00-0.620.340.350.16Construction

1.00-0.04-0.690.07Vacancies

1.00-0.330.96CPI

1.00-0.43Effect Rents

1.00Net Income

GSPEmploymentConstructionVacanciesCPIEffect RentsNet Income

Page 20: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Research – Property Market Forecast Models

• Numerous models developed by US and UK Researchers

• Models being tested with Brisbane CBD data• Issue with data availability• Optimum model to provide basis for

forecasting module in DCF software• Aim to generate forecasts for rents, vacancy

rates, construction activity, yields & discount rates

Page 21: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Market Forecast Example Equations

Net Space Absorption

ABt = τ1[α0 + Et[α1 + α2 (Et – Et-1) – α3Rt]] – τ1OCt-1

Et E = office based employmentR = office rentOC = occupied space

Page 22: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Market Forecast Example Equations

Rent

Rt = µ3(µ0 – µ1Vt-1 + µ2 ABt-1 ) – µ3Rt-1

St-1

V = vacancyAB = net absorptionS = stock of spaceR = rent

Page 23: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Market Forecast Example Equations

Construction – Space Supply

Ct = τ2 (β0 + β1St-8 + β2St-8Vt-8 + β3ABt-8) + (1 – τ2)Ct-1

S = stock of spaceV = vacancyAB = net absorptionC = construction

Page 24: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Risk Identification

What are the crucial inputs of the study?

For investment studies:What will the future rents be?What will the property sell for?What are the likely capital costs?

For development studies:What are the likely timings for approvals?What will the selling price/s be?What will the development costs be?Other issues…

Page 25: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Property Investment Crucial Variablesin Cash Flow Study

Rent Escalation Rates

Discount Rate

Terminal Capitalisation Rate

Loan Interest Rates

Purchase PriceIn certain circumstances

Page 26: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

RISK

Is described as the uncertainty surrounding the consequences of actions or decisions.

Definition:“The probability of not receiving what is expected”

PROBABILITY is often described as a deviation from the expected outcomes.

In financial terms the reward for committing funds is the RETURN and the uncertainty of receiving the expected return is the RISK.

Page 27: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Risk and Return Trade-Off

A higher return must be offered to attract investor’s funds to riskier investments.

Risk and expected returns must be balanced in investment decisions.

EXPECTED RETURN

RISK FREE….RATE

RISK

Page 28: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Types of Risk

Total investment risk is typically classified as systematic and unsystematic risk.

• Systematic risk – involves pervasive factors that effect all assets, it is unavoidable uncontrollable risk, e.g. inflation, interest rates, market cycles, political events, etc.

• Unsystematic risk - risk that is unique to the asset in question e.g. location, tenancy risk, financial risk, liquidity of asset, etc.

Total Risk = Systematic Risk + Unsystematic Risk

Page 29: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Basic Measures of Return and Risk

RETURN measure is expected or mean return

RISK measure is the standard deviation from the mean return

The standard deviation is the measure of dispersionfrom expected figure (large standard deviation meanshigh risk, while low standard deviation means low risk)

Page 30: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Combined Risk/Return Measures

1. COEFFICIENT OF VARIATION (CV)CV = std dev / mean

This is a ratio of the risk to expected return; it can be expressed as a percentage.

2. SHARPE INDEX= (Mean rate of return – risk free rate of return) / std dev of return

This is risk adjusted real rate of return

Page 31: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Sensitivity Analysis

Sensitivity Analysis : quantifies risk by a process of assigning different values to the inputs considered uncertain in a cash flow model, and then measuring their relative impact on important output variables such as NPV, PV, IRR

Page 32: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Case Study Example

Equity Study Sensitivity Analysis

17,200,000

17,300,000

17,400,000

17,500,000

17,600,000

17,700,000

17,800,000

17,900,000

18,000,000

18,100,000

18,200,000

18,300,000

18,400,000

18,500,000

18,600,000

-1.5% -1.0% -0.5% 0.0% 0.5% 1.0% 1.5%

Percentage Change

Inve

stm

ent W

orth

Interest Rate Discount Rate OPEX Rate Gross RentalSpider diagramUsed to measures the output change for a realistic change in that variable alone.This method does not take into account the correlation that might exist between the variables, but it is acceptable to determine the degree of sensitivity.

Page 33: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Tutorial on Sensitivity Analysis

What should you look at to determine the impact of the key variables on the final output?

Which one is the variable that has the strongest impact on the figure?

Which one has the lowest impact?

Page 34: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Scenario Analysis

Scenario Analysis : similar to sensitivity analysis but here the input variable values are grouped together at values assigned for different scenarios (e.g. boom, normal, and recession) and then the relative impact of the grouped changes is assessed.Output is most likely, best and worst case scenarios.

Page 35: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Simulation Analysis

Simulation Analysis : The probability distributions are estimated for each uncertain variable in a cash flow model and the possible combinations of all values for each factor are then simulated to determine the range of possible outcomes and the probability of each outcome.

Page 36: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Case Study: Simulation Exercise

7.75% 8.00% 8.25% 8.50% 8.75%

terminal cap

9.66% 9.93% 10.20% 10.47% 10.74%

disc rate

1.80% 2.40% 3.00% 3.60% 4.20%

Rental escalation 1

Page 37: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Simulation Exercise Diagram

Frequency Chart

Certainty is 86.90% from 108,000,000 to 115,000,000 $

.000

.008

.017

.025

.033

0

8.25

16.5

24.75

33

105,300,422 108,270,092 111,239,763 114,209,433 117,179,104

1,000 Trials 992 Displayed

Forecast: Market Value

Page 38: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Risk Management ProcessesAvoiding Risk1. Study property cycle - enter and exit at correct time.2. Selection property type (less risky).3. Prime location selection.4. Structure of financing - no loan finance.5. Quality tenants on secure leases.

Transferring Risk1. Insurance policies2. ‘Limited’ Company.3. No personal guarantees given.4. Good default clauses (easy, quick return of asset).5. Obtaining guarantees from lessee/buyer.6. Sharing interest in property.

Minimising Risk1. Reducing loan finance or interest burden.2. Lower purchase price, deferred payments.3. Rational diversification.4. Good accounting controls and reporting systems.5. Careful investment feasibility study.6. Improved project and property management.7. Improved tenants - ‘pre-let' situation.8. Prime location.9. Quality building.

Page 39: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Financial Performance Measures

Most probable return (or value/price)

The ‘standard deviation’ risk measure(or range of possible results)

Most sensitive input variables

What-if results

Financial ratiosLoan interest: net incomeLoan amount: value

Benchmark comparisons(to internal or external benchmarks)

Page 40: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Triple Bottom Line (TBL)

A valuer’s working definition – the comprehensive qualitative and/or quantitative assessment of social and environmental factors of agiven entity, complimentary to purely economic considerations.

Major principles – Legitimacy; appeal to common sense; longer-term focus (inter-generational equity); workplace equity; moral high ground.

Why value TBL – Reflect changes in the market (attitudes dictating demand & supply); important variables obscured by traditional economic approaches; sounder future value projections.

Major problems – Entity ‘greenwashing’; disclosure; difficult to quantify.

Solutions – Avoid ‘messy’ contingency valuations using an integrative, flexible approach (use $ + stars); pay particular attention to entities at the margins.

Page 41: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Social Metrics

… Developed from Global Reporting Initiative to suit case study

Working conditions• Disclosure of health and safety records• Level of training and awareness optimizing the use of building features• Provision and monitoring of equal opportunity features/amenities• Provision, if any, of facilities/amenities/lobby space/furniture for the publicSociety impacts• Management of stakeholder interests/impacts in local precinct• Nature of tenant and naming rights businesses• Insurance cover for workers, maintenance crews, and the general publicTransparency• Disclosure of management details, including staff, structure, salaries,

contract agreements, auditsHuman Rights• Details regarding human rights training for security personnel, ect. (if any)

Page 42: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

Environmental Indicators

… Selected from green building codes

• Impact of materials used (LCA Design or similar software)• Energy consumption (savings, efficiency, alternatives, ect.)• Energy consumption footprint (plan - total life cycle)• Water consumption (recycling, capture, wastewater)• Emissions (greenhouse, ozone, particulates ect.)• Wastes and effluents (recycling and/or removal)• Transport for workers and visitors (public transport, carpooling)• Non-compliance with environmental regulations • Quality of built environment (worker satisfaction, aesthetics ect.)

Page 43: Evaluating Risk in Property Feasibility Studies for NPV computation Year is the time interval t1…tn is the length of study tn+1 is the extra year NPV = (disc rate, CF2…CFn) + CF1

19 June, 2003 CRC CI Project 11

Questions ???

Evaluating Risk in Property Feasibility Studies