COST-BENEFIT ANALYSIS MODEL:

A TOOL FOR AREA-WIDE FRUIT FLY MANAGEMENT

Procedures Manual

Sponsored by the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture

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CONV. SIT-SUPP SIT-ERAD

US$

MN

Year

Net-Benefits

Wild hosts

Backyardhosts

PEST CONTROL ON AN AREAWIDE BASIS

(TOTAL POPULATION CONTROL)

Alternatecommercial crop

Commercial crop

Abandoned commercial crop

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FOREWORD

The Generic Fruit Fly Cost–Benefit Analysis Model assists in economic decision making associated

with area-wide fruit fly control options.

The Model is user friendly and thus largely self-explanatory. Nevertheless, it includes a procedures

manual that has been prepared to guide the user, and thus should be used together with the software.

Please note that the table presenting the pest management options in the Introductory Page of the

model is controlled by spin buttons and click boxes. These controls are linked to macros that hide non

relevant tables and boxes. N.B. it is important that the medium level of security is selected from the

Tools menu of Excel, to do this go to Tools|Macros|Security| and select Medium. When the file is

opened a form will appear containing three buttons, click on the middle button, “Enable Macros”, so

that the macros may be used.

Ideally the model should be used as a support tool by working groups aiming at assessing the

economic returns of different fruit fly control options (suppression, eradication, containment and

prevention). The working group should include professionals in agriculture with experience in area-

wide implementation of integrated pest management programmes, an economist or at least someone

with basic knowledge in economics, and if relevant, an entomologist with some background in the

application of the sterile insect technique (SIT).

The officer responsible for this software and procedures manual is W. Enkerlin of the Joint

FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture. The IAEA wishes to

acknowledge J. Mumford and A. Leach of the Department of Environmental Science and Technology,

Imperial College London, for their significant contributions to this model.

EDITORIAL NOTE

The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries.

The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA.

Every effort has been made to ensure that the information and the calculations contained within this program are correct. However the IAEA will not accept any liability for damage arising out of the use of the program or any information contained within the system or this manual. This program is protected by copyright laws.

CONTENTS

1. INTRODUCTION ........................................................................................................................1

2. SYSTEM OVERVIEW ................................................................................................................3

3. OPENING THE FILE...................................................................................................................5

4. DATA ENTRY .............................................................................................................................5

5. INTRODUCTORY PAGE............................................................................................................6

6. INPUT SHEET 1 ..........................................................................................................................6

7. INPUT SHEET 2 ..........................................................................................................................6

8. INPUT SHEET 3 ..........................................................................................................................7

9. UNIT COSTS................................................................................................................................8

10. PRODUCTION AND MARKET .................................................................................................8

11. SECONDARY COSTS.................................................................................................................9

12. BAIT SUPPRESSION (BAIT SUPP).........................................................................................10

13. SIT SUPPRESSION (SIT SUPP (BAIT + BIO)) .......................................................................11

14. SIT ERADICATION (SIT ERAD (BAIT) & SIT ERAD (BIO)) ..............................................13

15. ZONE COSTS ............................................................................................................................13

16. COST–BENEFIT ANALYSIS FOR BAIT SUPPRESSION (CBA BAIT SUPP) ....................13

17. COST–BENEFIT ANALYSIS FOR SIT SUPPRESSION (CBA SIT SUPP)...........................15

18. COST–BENEFIT ANALYSIS FOR SIT ERADICATION (CBA SIT ERAD).........................16

19. INPUT REQUIREMENTS.........................................................................................................16

20. SUMMARY TABLES................................................................................................................16

21. GRAPHS.....................................................................................................................................17

1. INTRODUCTION

The FRUIT FLY COST-BENEFIT ANALYSIS PROGRAM is an Excel 2000 Windows based

program, for which all standard Windows and Excel conventions apply. If you are not familiar with

Windows, we suggest that you check the Microsoft Windows manual for information about making

best use of the mouse to move around the program.

1.1. A few simple tips!

1. Help that is appropriate to the window that you are viewing is available by pressing the F1 key, the

Help option on the main menu or the Help button if there is one.

2. The only cells that may be added to or edited are highlighted in blue. Other cells that the user

attempts to edit will return an Excel warning window containing: “Protected Cell or Block”.

3. The program is controlled by clicking the left mouse button when the cursor is positioned over the

appropriate part of the screen. It is also possible to navigate between items on the menu by

pressing the ALT key and the letter that is underlined on the screen.

4. To close the Fruit Fly CBA program, single click the left mouse button when the cursor is

positioned over the “x” square in the top right corner of the screen or press the ALT and F4 key at

the same time.

1.2. Installation What you need: a. Windows version 95 or later. b. IBM PC with Pentium microprocessor and at least 32MB RAM (the faster the processor the

better).

c. CD ROM Drive. The disks you have received have everything you need to run the Generic Fruit Fly CBA program.

Before installing the program please make a backup copy of the disks. If you do not know how to do

this consult your DOS or Windows manuals.

To install the program: a. Start Windows. b. Insert Fruit Fly CBA CD into the appropriate drive.

1

c. Access the File Manager or Windows Explorer and double click on Fruit Fly CBA.exe file. d. This will automatically unzip itself to a directory called c:\Fruit Fly CBA. e. Start Excel 2000 (or later version) and open the file called Fruit Fly CBA.xls from the File menu. This manual is not designed to teach the reader cost–benefit analysis techniques but rather to guide the

user through the program, indicating where inputs are required so that a benefit\cost analysis for fruit

fly management may be easily derived. Use the manual simultaneously with data input; moving from

section to section in the manual as you move page by page through the spreadsheet model.

It is suggested that the user read the papers:

Enkerlin, W. R. and J. D. Mumford, 1996. Estimation of economic returns of alternative components

of management of the Mediterranean fruit fly (Ceratitis capitata Wied) in Israel, Palestine and Jordan.

Report to IAEA. Technical contract 8441/RB. Vienna, Austria. 40pp.

Enkerlin, W. R. and J. D. Mumford, 1997. Economic Evaluation of Three Alternative Methods for

Control of the Mediterranean Fruit Fly (Diptera: Tephritidae) in Israel, Palestinian Territories, and

Jordan. J. Econ. Entomol. 90(5): 1066-1072.

FAO. 1984. Economic guidelines for pest control. Plant Protection Paper 58, Rome, Italy. 93pp.

Mumford, J. D., A. Driouchi, W. R. Enkerlin, G.A. Carlson, and E.J. Buycx, 1995. Economic

evaluation of damage caused by and methods of control of, the Mediterranean fruit fly in the Mahgreb.

IAEA-TECDOC-830, IAEA, Vienna, Austria. 68pp.

Hendrichs, J., M. J. B. Vreysen, W. R. Enkerlin, and J. P. Cayol, 2005. Strategic Options in Using

Sterile Insects for Area-Wide Integrated Pest Management. In V. A. Dyck, J. Hendrichs and A. S.

Robinson (eds.), Sterile insect technique. Principles and practice in area-wide integrated pest

management. Springer, Dordrecht, Netherlands.

Quinlan, M. M. and W. Enkerlin, 2003. The Commercialization of SIT. In "Recent Trends on Sterile

Insect Technique and Area-Wide Integrated Pest Management, Economic Feasibility, Control

Projects, Farmer Organization and Bactrocera dorsalis Complex Control Study " Book published by

Research Institute for Subtropics, Naha, Japan. 122 pp.

2

2. SYSTEM OVERVIEW

The program is designed to be used by teams investigating the relative merits of different fruit fly

management strategies for a selected region.

The program is designed to allow the user to compare three basic fruit fly management systems on the

basis of economic cost–benefit relationships. The three management systems that the model allows

the user to compare are:

a. Bait Suppression (BAIT SUPP)

Controlling flies by luring them to pesticide treated baits reducing populations to sub-

economic levels.

b. SIT Suppression (SIT SUPP)

The sterile insect technique (SIT) is the main component of an area-wide integrated pest

management programme. Apart from sterile insects this pest management option includes:

population survey, and other control methods, namely, insecticide-bait sprays, biocontrol agents

and post harvest treatments. Sterile males are continuously released competing with wild (fertile)

males for mates resulting in females producing eggs that are not viable, reducing populations to

sub economic levels. This option requires continuous use of sterile flies to keep population levels

below the set threshold. Thus in the long term it is a more expensive option than SIT eradication.

The main advantage of this control option is that insecticide use is substantially reduced

contributing to reduced environmental and human health costs. Moreover, fruits and vegetables

produced under this pest control scheme can have access to export markets that discriminate for

insecticide residues.

c. SIT Eradication (SIT ERAD)

As for SIT suppression, nevertheless, higher densities of sterile males are required to achieve

eradication than for SIT suppression but the process is complete in a relatively short time. The

primary advantage is that once fly free status is achieved no further management is required other

than quarantine and monitoring so that accidental introductions can be eradicated quickly. Fruit

fly eradication in a zone or region requires fruit fly suppression prior to the start of eradication to

reduce populations to levels where adequate sterile:fertile rations can be obtained to eradicate

populations after a few generations. This option generates the greatest benefits as, apart from

eliminating the use of insecticides, it also eliminates the pest. This combined effect allows fruits

3

and vegetables produced under this control option to have access to export markets that

discriminate against pesticide residues and pests. However, this option due to the scale and

intensity of the intervention, requires higher initial capital investment. In addition, this is a higher

risk option as fruit fly free areas are constantly subjected to re-introductions of the pest and thus to

loosing the phytosanitary status. To reduce the risk, stringent quarantine measures need to be in

place as well as a solid emergency reaction plan.

This control option is divided into two approaches which are: 1) SIT eradication (SIT ERAD

(BAIT)) with an insecticide-bait component and 2) SIT eradication with combined insecticide bait

and biocontrol components (SIT ERAD (BIO)).

2.1. Geographical levels

The computer system allows the user to define three geographic “levels”. These are, from largest to

smallest: Regions, Countries and Zones (see INPUT SHEET 1). The Zone is the working unit of the

model. Thus, when strategies for each Zone are designated analyses can be conducted based on user-

defined combinations of zones to provide economic indices for each strategy at Country and/or

Regional levels. For example, in cost benefit exercise of this type the Middle East was classified as a

region, which comprised four countries (Israel, Territories Under the Jurisdiction of the Palestinian

Authority, Lebanon and Jordan) and each of the countries was then subdivided into different numbers

of zones depending on the biogeographic characteristics of the area, pest distribution and abundance

and infrastructure of each country. Nevertheless, should a user wish to work at a higher resolution a

country could classify as a region, e.g. the Lebanon, and this again would be divided into zones

appropriate to its area and infrastructure.

2.2. Components of the model

The spreadsheet model is set out in a series of “sheets” that contain individual components of the

model. These are kept in separate pages of the model to make editing and use easier and more

understandable.

The Market and Production and Unit Costs page requires basic inputs regarding market volumes and

prices, production volumes, pest damage, control actions and unit costs for the surveillance and

control techniques. In the BAIT SUPP, SIT SUPP and SIT ERAD pages the user(s) is required to

enter the different techniques for each zone over time. The model has a potential to simulate the

introduction of techniques up to twenty years for up to ten zones. Each of these pages is summarised

in the Zone Cost page.

4

Economic analyses for each of the strategies are conducted on each of the BCA BAIT SUPP, BCA

SIT SUPP and BCA SIT ERAD pages. These require the user to enter the number of years over which

the analysis is to be conducted, the economic discount rate for the region and the zones that are

contained within each country (should there be more than one country in a region). The Input

Requirements page then shows the user the resource allocation needs for each of the potential

techniques. The output data for all techniques and control options is collected on the Summary Page

that is followed by a page that represents key outputs graphically (Graphics Page).

3. OPENING THE FILE

When first opening the original file it is very important that it is saved under a new name so that the

empty original document is kept in an unaltered form so that it can be used for future projects. It is

also important to make back ups of the original file and also files that are being worked on so that in

the event of accidents there is always an up to date copy of the work available.

The file contains macros. It is important that the medium level of security is selected from the Tools

menu of Excel; to do this go to Tools|Macros|Security| and select Medium. When the file is opened a

form will appear containing three buttons. Click on the middle button, “Enable Macros”, so that

macros may be used.

From Excel open the file “Fruit Fly CBA” from the directory into which the program was copied

(File/Open/). Immediately save this file as a new name by using the File/Save As. For example, if

you were performing a benefit\cost analysis exercise for fruit flies in the Middle East you might save

the file as “MidEast” in a folder (or directory) called “CBAMed”.

4. DATA ENTRY

On opening the file for the first time you will be prompted to enable or disable the macros in the

Excel. If you are certain that the file has come from a good source and that up-to-date virus checking

software is operating on your system then you should enable Macros so that you can view the

Introduction page and the Necessary Information pages. Some cells are tinted blue. These are input

cells into which information must be added (note that many times only zeros or blanks will be

needed). The manual will address each Spreadsheet page as a separate section.

5

Clicking on the tabs at the bottom of the screen allows the user to move between pages. Some tabs

may be obscured to the left or the right of the viewed tabs and the arrows to the left of the tabs allow

the user to scroll through the list.

The following sections contain a brief explanation of the different pages of the Excel model.

5. INTRODUCTORY PAGE

In this page please enter the discount rate as a decimal e.g. if the bank rate is 8% then please enter the

value as 0.08 or a discount rate of 12% as 0.12 etc. Four check box controls are also on this page; one

four each control method that the model can evaluate, uncheck any techniques not required in the

evaluation and macros will hide irrelevant sheets, graphs and tables.

6. INPUT SHEET 1

This input page allows the user to specify the numbers and size of zones that the Fruit fly management

option will use. Choice of zone size may depend on the infrastructure, geography and political

boundaries involved in the region. Zone areas must be specified in km2. These will later be

automatically converted into hectares by the model.

There could be more than one country in a region. One country can have one or more zones. The name

of the country should be added in the column beside each zone starting at C8.

7. INPUT SHEET 2

At the top of the sheet are two cells (C1 and G4) that require the entry of the Region name and the

year in which the data was entered into the model. When these have been completed these cells are

used as references by many other pages in the spreadsheet.

This page is made up of two tables per zone in which data must be added and two tables in which data

may, optionally, be added. The agricultural data for each zone can be added by scrolling down the

page to each zone. The model allows for two types of agriculture to be stipulated, namely high and

low input. It is up to the user to define the classes if such classifications are necessary. Countries may

be comprised of high input only, low input only, or combinations of each for each commodity. Each

zone has its own set of tables listed vertically and each zone can be given its own name on Input Sheet

3 that are automatically referenced by cells on this and other sheets within the workbook.

6

The first table starts at B10 and deals with area, yield, production (calculated by multiplying area and

weighted averages of yield) and the value of production (based upon multiplication of price with

production). Data on area, yield and price must be entered for each major commodity for the Region.

This may require the user to do some simple calculations to provide weighted prices or yields where

there are differences in these within countries included in a region.

The second table starts at cell T10 and requires estimates of potential loss (if no pest management is

utilised) and actual damage (the damage caused by fruit fly despite management practices) caused by

the fruit fly in each of the commodities. This requires field data and/or expert opinion to ensure that

realistic values are entered. The model then calculates the actual and potential value of this loss for

each commodity.

The third and fourth tables starting at cells AM10 and BC10, respectively, are not used directly by the

model but are included because they can help the user to understand the problem better in some cases

(if they are completed). The first is a table where seasonal damage for each commodity, caused by the

fruit fly, can be entered. For each month the percentage of total damage caused by fruit fly for the

year should be entered. This will allow the user to visualise the fruit fly problem through time and so

see the impact of pest management strategies. The fourth table is the projection of planted area for a

specified time into the future. This allows the user to estimate the potential impacts of the fruit fly

problem with increasing, or decreasing areas of certain commodities.

8. INPUT SHEET 3

The model has made the assumption that the region has no fly free area certificated exports. Any fly

free certified exports because of post harvest treatment should be included in the fly-free certified

export class. If there are no exports of any kind, i.e. the domestic market absorbs all regional fruit

production, then zeros should be put into each of the blue cells ranging from C8 to C21.

Cells J6 ask the user to enter multiples of the domestic market prices for sales into each of the export

categories. For example if the user entered 1.5 into cell K8 this would mean that sales of fruit into the

fly free certificated export market would have prices 1.5 times that of the domestic market. The same

is the case for cell L8 (non fly-free exports). Values of 1.0 entered into these cells indicate that there

is no increase in value of these exports compared with domestic market prices.

The model allows the user to perform some sensitivity analysis based on increased or reduced amounts

of fruits under the new market category (values can be altered in F8 to F13 for export markets).

Values of zero indicate that the shares in domestic or export markets have not increased. Sensitivity

7

analysis for prices of the fruit commodities can be conducted by entering increased or reduced values

(values can be altered in P8 to P13 and Q8 to Q13). Sensitivity analysis should only be performed

after all the data has been entered, the effects on the economic indices for each strategy should be

noted.

9. UNIT COSTS

The unit costs page allows specific costs of the different techniques to be broken into their

components. For example each trap type is included and every trap service can be costed for labour,

vehicle cost (fuel and maintenance), the trap and its components, the cost of the lure and the

insecticide. When totalled (which is performed automatically), each subsection provides a unit cost

for each set of activities. Each fruit fly management strategy has different activity requirements and

the model calculates the cost of each activity based upon the unit costs entered into this page.

In the table starting at cell H55 the user must enter information relating to bait spraying methods. In

cell I58 enter the proportion of the total “orchard area” that will have bait applied to it “aerially” and

in I61 the proportion of the total “urban and other areas” surface area that will have bait spray applied

to it “aerially”. For each of the options (orchard and [urban and other areas]) the proportion of the

area that will be sprayed by “ground based treatments” is calculated automatically (1- proportion

entered for aerial). For example if ground based only is used in orchards then zero should be entered

at I58 (the cell for proportion of area applied aerially).

10. PRODUCTION AND MARKET

The production and market model calculates production, damage and monitoring and control variables

based on the information added to the model in Input Sheet 1 and Input Sheet 2. This page also allows

for the addition of indirect costs (Cell L75) of pesticide use through treatments to human poisonings,

loss of honey yield and revenue through insecticide based bee mortality and resurgence of secondary

pests because of spray drift.

In cells C23 to D23 the user is required to enter the current number of sprays used in each fruit class

for high and low input agriculture. In the cell G20 the cost of pesticide application per hectare should

be added.

8

Trap services, cost and density data must be added to the cells F32 to G37. The value for the cost

should be taken from the Unit Cost page based on the choice of traps used in the region. If

combinations of traps are used it is necessary for the user to provide a weighted average (WA) of trap

cost in cell G29. This may be done by calculating using the formula:

WA = ((c1 n1) + (c2 n2) + (c3 n3) + (c4 n4)) / (n1 + n2 + n3 + n4)

Where c1 to c4 are the costs for each trap type and n1 to n4 are the number of each trap used.

11. SECONDARY COSTS

This worksheet refers to secondary costs of the current pest management system. If, for example, the

current management strategy is entirely pesticide cover sprays of orchards then the secondary costs of

losses of honey, pesticide poisonings and secondary pest outbreaks could be high and should be added

to the benefits of using an improved alternative to cover sprays. It is important that some attempt is

made to estimate and enter these costs.

At cell A3 there is a table of indirect costs of fruit fly control. It is not necessary to add information to

this section if it is not available, but at the final analysis the exclusion of secondary costs may make

the CURRENT management scenario, if it is pesticide based, appear more favourable than it is in

reality because the full environmental costs of pesticide use will not have been calculated.

The first subsection deals with indirect costs attributable to secondary pest outbreaks following spray

drift. In cell E8 it is necessary to add a frequency (as a proportion) with which natural enemy

mortality occur following spray drift and in E14 the frequency of no natural enemy mortality

occurring. The sum of E8 and E14 should always be equal top one. In cell E9 add the probability of a

secondary pest outbreak occurring following natural enemy mortality and in cell E13 the probability of

no natural enemy mortality occurring. The sum of E9 and E13 should always be equal to one. In D11

and D12 the user should enter the percent crop loss that would occur if farmers respond, or not, to

secondary outbreaks by spraying and in E11 and E12 the frequency of the event occurring.

The second subsection of the Secondary Costs table (A20) requires data regarding losses associated

with reduced honey production. Agricultural expertise may be required to make reasonable

assumptions if field data is not available for this section.

The third subsection (A34) deals with the economic impact of pesticide use on human health. The

cost per treated person (A39) should be calculated for pesticide application personnel only (general

9

public poisonings being relatively rare usually). The average cost per treated person should be

calculated as follows:

Cost per treated person = (CA * NA) + (CH * NH) + (CW * NW)

Where:

CA = Cost of each atropine injection ($)

NA = Average no. of atropine injections per person

CH = Hospital fee per day ($)

NH = Average no. of days in hospital per person

CW = Average daily wage of pesticide application personnel ($)

NW = Average no. of days lost (hospital and home)

12. BAIT SUPPRESSION (BAIT SUPP)

This sheet will not be visible if the “Insecticide-Bait Suppression” check-box on the Introductory Page

worksheet is unchecked.

Each of the BAIT SUPP, SIT SUPP and SIT ERAD pages follows a similar format. At the top of each

page is the unit requirement for each technique (F9 to F41). Experts with experience in each of the

relevant sections should fill out this section.

Underneath this are tables that only require that the strategy for that zone be specified for each year

(the string of blue boxes) (F62 to Y62). Each zone has its own table. The table for Zone 2 is below

the table for Zone 1 and so on for Zones 3 to 10.

For BAIT SUPP only one strategy may be specified. The syntax of each strategy is very important.

The user must type in BAIT SUPP (for bait suppression). For SIT SUPP there are four possible

strategies (CURRENT, PRE SUPP, SUPP1 and SUPP2). For SIT ERAD there are five possible

strategies (CURRENT, PRE ERAD, ERAD, POST ERAD and FLY FREE). This allows for the

phasing in of strategies. Whilst this may not be an important consideration for bait suppression it may

be important for SIT suppression and SIT eradication where a strategy may not be implemented in all

zones at the same time. Enter the selected text strings of strategies for the full twenty years for each

zone. The time horizon (the intended duration of the management project) can be manipulated by

changing the number of years in the Introductory Page (F17) so that the sensitivity of the output to

changes in time horizon can be observed for each strategy.

10

The spelling and spacing of letters in the words are vital for the model to work. Other words entered

into these spaces (including misspellings) return zeros. CURRENT also returns zeros at this point as

the costs for this option are calculated elsewhere. However, the model is not case sensitive so that

“BAIT SUPP” written as “Bait Supp” or “bait supp” will give the same output.

13. SIT SUPPRESSION (SIT SUPP (BAIT + BIO))

This sheet will not be visible if the “Area-wide SIT Suppression” check-box on the Introductory Page

worksheet is unchecked.

This page follows an identical format to that of the previous BAIT SUPP page. The principal

difference is that the unit requirement table (starting at C4) now has three classes which require data

i.e. PRE SUPP (pre suppression), SUPP 1 (early suppression), SUPP 2 (full / late suppression). Data

has been left in these unit requirement cells as a template. The user should make any changes that fit

local cases.

The user should add the anticipated management strategy for each Zone. The main variation (from the

previous page) is that there are four management options that should be specified. These are

CURRENT, PRE SUPP, SUPP 1 and SUPP 2. Again, enter one of these text strings in the cells (F69

to Y69, F165 to Y165, etc.) for the full twenty years for each zone.

It is the responsibility of the user to phase the introduction of the strategies for each zone logically so

that the phasing is conducted in the most efficient way. Example: If we consider a region such as

North Africa where there is sea on the north side and desert to the south then the phasing should go

from east to west or west to east. If we, hypothetically separated the whole of the North African coast

into seven zones running from west to east, each zone would be numbered 1 to 7 from west to east and

a logical progression of SIT suppression strategies (using a ten year time horizon) is shown in Table 1.

In this case we have made the assumption it was only possible to start suppression in one zone at a

time whereas it may be that it is possible to start suppression in two zones simultaneously or that one

zone a year is actually too difficult and may be implemented over several years i.e. two years of “pre

suppression” may be required. The model is flexible enough to cope with any strategy but it the

responsibility of the user to ensure that the strategy that is entered is both logical and feasible.

11

TAB

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ses o

nly

a te

n ye

ar h

oriz

on a

s an

exam

ple.

In

the

SIT

SUPP

pag

e th

e co

des (

CU

RR

ENT,

PR

E SU

PP, S

UPP

1 o

r SU

PP 2

) mus

t be

adde

d fo

r the

fu

ll tw

enty

yea

rs.

12

14. SIT ERADICATION (SIT ERAD (BAIT) & SIT ERAD (BIO))

The general format for this pages is the same as the previous two pages but there are now four options

to complete in the unit requirement section (F6 to I6) and five strategies that should be added to the

zone strategy section (starting at F69 for SIT-ERAD (BAIT)) and F89 for SIT-ERAD (BIO)). The

five strategies that can be added by the user are CURRENT, PRE ERAD (Pre-eradication), ERAD

(Eradication), POST ERAD (Post eradication) and FLY FREE (Fly free status is achieved). These

must be entered for all the zones to be included in the model and for every year in each zone.

Using the same hypothetical scenario as for the previous (SIT suppression) page an example of an

implementation strategy can be seen in Table 2.

The SIT ERAD (BIO) sheet for SIT allows the user to specify bio-control based parasitoid releases as

a suppression method in conjunction with sterile fly releases.

15. ZONE COSTS

The Zone Costs page summarises the costs of the specified activities for each zone. CURRENT costs

are NOT included in this page. The only user inputs that this page requires are capital costs for SIT

suppression and eradication. There are two classes of capital costs which are SIT factory building

costs which are single capital items and Other Capital Costs which can include any user defined costs

such as buildings for packing and holding sterile flies, etc. Other Capital Costs can be specified for

any year throughout the time horizon of the analysis. All the costs on this page are in millions of US

dollars.

16. COST–BENEFIT ANALYSIS FOR BAIT SUPPRESSION

(CBA BAIT SUPP)

The CBA pages are where the data entered by the user start to be analysed so that the benefit-cost

analysis of a particular strategy and other economic indices are calculated.

13

TAB

LE 2

. TE

N Y

EAR

HY

POTH

ETIC

AL

ERA

DIC

ATI

ON

STR

ATE

GY

FO

R N

OR

TH W

EST

AFR

ICA

(DIV

IDED

INTO

SEV

EN Z

ON

ES)

Y

ear

1

2

3

4

5

6

7

8

9

10

Zone

1

PRE

ER

AD

E

RA

D

POST

ER

AD

FL

Y F

RE

E

FLY

FR

EE

FLY

FR

EE

FL

Y F

RE

E

FLY

FR

EE

FLY

FR

EE

FLY

FR

EE

Zone

2

CU

RR

EN

T PR

E E

RA

D

ER

AD

PO

ST E

RA

D FL

Y F

RE

E FL

Y F

RE

E

FLY

FR

EE

FL

Y F

RE

E FL

Y F

RE

E FL

Y F

RE

E

Zo

ne 3

C

UR

RE

NT

CU

RR

EN

T PR

E E

RA

D

ER

AD

PO

ST

ER

AD

FL

Y F

RE

E

FLY

FR

EE

FL

Y F

RE

E FL

Y F

RE

E FL

Y F

RE

E

Zo

ne 4

C

UR

RE

NT

CU

RR

EN

T

CU

RR

EN

T

PR

E E

RA

D

E

RA

D

POST

ER

AD

FL

Y F

RE

E

FLY

FR

EE

FLY

FR

EE

FLY

FR

EE

Zone

5

CU

RR

EN

T C

UR

RE

NT

C

UR

RE

NT

CU

RR

EN

T

PRE

ER

AD

E

RA

D

POST

ER

AD

FLY

FR

EE

FLY

FR

EE

FLY

FR

EE

Zone

6

CU

RR

EN

T C

UR

RE

NT

C

UR

RE

NT

CU

RR

EN

T

CU

RR

EN

T PR

E E

RA

D

ER

AD

PO

ST E

RA

D FL

Y F

RE

E FL

Y F

RE

E

Zo

ne 7

C

UR

RE

NT

CU

RR

EN

T

CU

RR

EN

T

C

UR

RE

NT

C

UR

RE

NT

CU

RR

EN

T PR

E E

RA

D

ER

AD

PO

ST E

RA

D FL

Y F

RE

E

Not

e.- T

his u

ses o

nly

a te

n ye

ar h

oriz

on a

s an

exam

ple.

In

the

SIT

ERA

D p

age

the

code

s (C

UR

REN

T, P

RE

ERA

D, E

RA

D, P

OST

ER

AD

or F

LY F

REE

) mus

t be

add

ed fo

r the

full

twen

ty y

ears

.

14

In cell F14 of the Introductory Page the time horizon over which the analysis will be projected should

be entered (for maximum twenty years). It is, perhaps, more appropriate to be pessimistic about the

duration of projects. The political or economic stability of an area should be taken into consideration

when deciding on the length of time for which a strategy should be projected. Projections of durations

much greater than 12 years should be made only where the user judges the region to be fundamentally

stable and where the political will for an area-wide fly control programme may be maintained. The

higher the discount rate the more unstable the economic / political climate, so this serves as an extra

guide to the duration to consider in an analysis.

The model allows for economic analyses to be conducted for zones/countries (starting at F38). The

data for each zone is automatically added to the adjacent cells and totalled at the bottom of each block

to give economic indices for each zone/country.

Unless the zone is actually a zone as in the Central America example supplied then the model cannot

calculate the overall benefit-cost ratio for a country given the huge potential number of combinations

of zones that would need to be accommodated. If the user wishes to calculate the benefit-cost ratio for

a whole country made up of several zones it is a simple procedure. For example, if a country

contained Zones 4 and 5 then the user should consult the “By Zone” table at E36 and then total up the

gross benefits for each zone in the country (e.g. Zones 4 and 5). Then sum the values in I41 and I42

that correspond to the cost for each zone. Once the sum of Gross Benefits and Costs for a country are

calculated, subtract the summed gross benefits from costs and this will produce the net-benefits. Then

divide the summed gross benefits by the summed costs and this will produce the benefit-cost ratio for

that country. The same procedure should be used for calculating the net-benefits and benefit-cost ratio

in the CBA SIT SUPP (BAIT + BIO), CBA SIT ERAD (BAIT) and CBA SIT ERAD (BIO) pages. If

the country is made up of a single zone then the value given in the “Indices By Country” table at H37

and J37 will be correct without further calculation by the user.

17. COST–BENEFIT ANALYSIS FOR SIT SUPPRESSION

(CBA SIT SUPP)

Most of the information added by the user in the CBA ERAD page is automatically transferred to the

CBA SIT SUPP and CBA SIT ERAD pages. This reduces the number of inputs the user must make

thereby reducing input errors.

15

Only one block on this page requires user inputs. These are D122 to D127 where expert opinion is

required to anticipate the increase in market share following the SUPP 1 phase of the strategy. Values

have been left in the cells to give an indication of possible increase in market share but should be

changed if it is anticipated that market gain would occur faster or slower than that shown.

The benefit cost ratio for a country within a region should be calculated as described in the final

paragraph of the previous section although the addresses, given in the example, for individual cells

will differ.

18. COST–BENEFIT ANALYSIS FOR SIT ERADICATION

(CBA SIT ERAD)

The only user inputs required for this page are for increased market share section at D116 to D125 for

CBA SIT-ERAD (BAIT) and at C117 to C126 for CBA SIT-ERAD (BIO) worksheets. New market

access only occurs after the POST ERAD phase is reached (due to “Fly Free” status).

The benefit cost ratio for a country within a region should be calculated as described in the final

paragraph of the CBA BAIT ERAD section.

19. INPUT REQUIREMENTS

The input requirements page catalogues the amount of inputs for each control option over the time

horizon specified on the Introductory Page. This page gives project coordinators the ability to plan

resources and finances for each of the techniques and control options tested. There are no inputs for

this page. Only options check boxed on the Introductory Page worksheet will show up.

20. SUMMARY TABLES

The Summary Tables page summarises the economic indices output of the model onto one page.

There are no inputs for this page. Only options check boxed on the Introductory Page worksheet will

show up.

The indices are represented in a matrix that allows decision makers and donors to compare the

economics of implementing various strategies.

16

21. GRAPHS

The graphics page is constructed to summarize the model output visually. Twelve graphs are shown

and display regional based model outputs. This page is locked so users wishing to create their own

graphs they should do so by inserting a new worksheet (menu Insert|Worksheet).

17