ISO/IEC 20968:2002

Software engineering — Mk II Function Point Analysis — Counting Practices Manual

ISO/IEC 20968:2002 specifies the set of definitions, conventions and activities of the MkII FPA Functional Size Measurement Method. The method can be used to measure the functional size of any software application that can be described in terms of logical transactions, each comprising an input, process and output component. The sizing rules were designed to apply to application software from the domain of business information systems, where the processing component of each transaction tends to be dominated by considerations of the storage or retrieval of data. The method may be applicable to software from other domains, but the user should note that the sizing rules do not take into account contributions to size such as from complex algorithms as typically found in scientific and engineering software, nor do the rules specifically take into account real-time requirements MK II FPA is independent of the project management method to be used and of the development method employed. It is a measure of the logical, business requirements, independent of how they are implemented.

Génie logiciel — Analyse des points fonctionnels Mk II — Manuel des pratiques de comptage

General Information

• Status: Published
• Publication Date: 24-Nov-2002
• ICS: 35.080 - Software
• Technical Committee: ISO/IEC JTC 1/SC 7 - Software and systems engineering
• Drafting Committee: ISO/IEC JTC 1/SC 7 - Software and systems engineering
• Current Stage: 9060 - Close of review
• Completion Date: 02-Dec-2030

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 20968
First edition
2002-12-01
Software engineering — Mk II Function
Point Analysis — Counting Practices
Manual
Génie logiciel — Analyse des points fonctionnels Mk II — Manuel des
pratiques de comptage
Reference number
©
ISO/IEC 2002
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©  ISO/IEC 2002
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ii © ISO/IEC 2002 — All rights reserved

Table of Contents
TABLE OF CONTENTS III
FOREWORD V
1 1
INTRODUCTION 1
1.1 Definition and Purpose of MkII Function Point Analysis 1
1.2 Purpose of the Counting Practices Manual (‘CPM’) 2
1.3 Who should read this document ? 2
1.4 Albrecht/IFPUG Function Point Analysis 2
1.5 Applicability of Mk II FPA 3
1.6 Manual Structure 4
1.7 Metrics Practices Committee 5
1.8 Procedure for raising a Query or Issue with the MPC 5
2 7
THE MK II FUNCTION POINT ANALYSIS RULES 7
Rule 1 Boundary 7
Rule 2 Functional Size and Logical Transactions 7
Rule 3 Processing Component of Logical Transactions 8
Rule 4 Input and Output Components of Logical Transactions 8
Rule 5 Logical Transaction Size 8
Rule 6 Reporting a MkII Function Point Count 9
3 11
MEASUREMENT STEPS 11
Step 1 Determine the Viewpoint, Purpose and Type of the Count 12
Step 2 Define the Boundary of the Count 12
Step 3 Identify the Logical Transactions 13
Step 4 Identify and Categorise the Data Entity Types 13
Step 5 Count the Input Data Element Types, the Data Entity Types Referenced, and the Output

Data Element Types. 13
Step 6 Calculate the Functional Size 13
Step 7 Determine Project Effort 13
Step 8 Calculate Productivity and other Performance Parameters 13
Step 9 Score the Degrees of Influence 13
Step 10 Calculate the Technical Complexity Adjustment 13
Step 11 Calculate Adjusted Size and Performance Parameters 14
4 15
GENERAL GUIDELINES FOR MKII FUNCTION POINT COUNTING 15
4.1 Determining the Viewpoint, Purpose and Type of the Count 15
4.2 Drawing the Boundary for a Count 16
4.3 Interfaces 18
4.4 Identifying Logical Transactions 21
4.5 Identifying Entity Types 39
4.6 Identifying Input and Output Data Element Types 43
© ISO/IEC 2002 — All rights reserved iii

5 49
MEASUREMENT GUIDELINES FOR SPECIFIC SITUATIONS 49

5.1 Counting Graphical User Interfaces (GUIs) 49
5.2 Approximate Sizing of Application Portfolios 54
5.3 Sizing Changes 55
5.4 Changes to make software Year 2000 compliant 58
5.5 Counting Application Packages 58
6 61
CALCULATING THE ADJUSTED SIZE (OPTIONAL) 61
7 63
MEASURING EFFORT 63
7.1 Project Start 64
7.2 Project End 64
7.3 Whose time included? 64
7.4 What time is included? 64
7.5 Project duration 64
8 65
MEASURING PRODUCTIVITY AND OTHER ASPECTS OF PERFORMANCE 65
8.1 Development Productivity 65
8.2 Change Productivity 65
8.3 Maintenance and Support Productivity 65
8.4 Measuring and Understanding Performance in Software Activities: The Wider Issues 66
9 68
ESTIMATING EFFORT USING MKII FPA 68
10 70
GLOSSARY OF MKII FPA TERMS 70
APPENDIX I 74
TECHNICAL COMPLEXITY ADJUSTMENT 74
APPENDIX II 84
DATA COLLECTION FORMS 84
Introduction 84
Record Sheets - a Possible Structure 84
Documentation Process 85
APPENDIX III 92
BIBLIOGRAPHY 92
The International Standard: 92
General texts on software measurement with MkII FPA: 92
Use of MkII FPA in Estimating 92
Other Relevant Publications 92

iv © ISO/IEC 2002 — All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 20968 was prepared by the United Kingdom Software Metrics Association (UKSMA) and was
adopted, under the PAS procedure, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in
parallel with its approval by national bodies of ISO and IEC.

© ISO/IEC 2002 — All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 20968:2002(E)

Software engineering — Mk II Function Point Analysis —
Counting Practices Manual
Introduction
1.1 Definition and Purpose of MkII Function Point Analysis
For the purposes of this document, the abbreviation ‘Mk II FPA’ is used for ‘Mark II
Function Point Analysis’.
Mk II FPA is a method for the quantitative analysis and measurement of information
processing applications. It quantifies the information processing requirements
specified by the user to provide a figure that expresses a size of the resulting
software product. This size is suitable for the purposes of performance
measurement and estimating in relation to the activity associated with the software
product
In the context of Mk II FPA, ‘information processing requirements’ means the set of
functions required by the commissioning user of the application software product
(excluding any technical and quality requirements). ‘The activity’ could be the
development, enhancement or maintenance of the software product needed to meet
the requirements.
The MkII FPA method is intended to comply with ISO/IEC 14143-1: 1998, the
International Standard for Functional Size Measurement (see Bibliography).
ÓISO/IEC 2002 – All rights reserved 1

1.2 Purpose of the Counting Practices Manual (‘CPM’)
The Mk II Method of Function Point Analysis was defined by Charles Symons in
"Software Sizing and Estimating: Mk II FPA" published in 1991. After development
within KPMG in 1985/86, with the protected status of a proprietary method, the
method is now in the public domain. The Metrics Practices Committee (MPC) of the
UK Software Metrics Association is now the design authority for the method and is
responsible for its continuing development.
The purpose of this Manual is to explain and promulgate the method, and to set out
the rules for applying Mk II Function Point Analysis (‘FPA’). Chapters 1 to 5 inclusive
of this manual provide the authoritative standard of the Mk II FPA Method.
It is not the purpose of this manual to replace Charles Symons' or the other books in
the Bibliography. The manual is not intended to provide a teaching introduction to MkII
FPA, nor does it discuss the broader subject of software measurement.
This manual replaces all previous versions of the Counting Practices Manual.
The definition covers:
· The software domains for which MkII FPA may be applicable
· Application software requirement components recognised by Mk II
FPA
· A process for applying the MkII FPA rules and documenting the
result
· Interpretation of the rules for a variety of software technologies (e.g.,
GUI, client/server, objects, etc.)
· Basic Formulae used in Mk II FPA
· Terminology used in Mk II FPA.
An important aspect of this new version of the standard, in order to comply with
ISO/IEC 14143-1:1998, is that the Technical Complexity Adjustment is no longer
considered to contribute to the "Functional Size". Hence measurements previously
expressed in MkII ‘Unadjusted Function Points’ should now be regarded as the MkII
measures of the Functional Size, without further qualification. For the time being, the
Technical Complexity Adjustment remains part of the method. If it has been applied
then the result should be qualified as the "Adjusted Size".
1.3 Who should read this document ?
· Users of Mk II FPA
· Suppliers of tools, training or other services involving the method.
· Anyone interested in learning about the details of Mk II FPA
1.4 Albrecht/IFPUG Function Point Analysis
Allan Albrecht developed the original Function Point Analysis method. The design
authority for the direct descendent of his approach is now the International Function
Point Users Group (‘IFPUG’). The briefest reference is made here to the relationship
between the Mk II and the IFPUG FPA methods.
The two methods measure subtly but significantly different sizes of a software
product (and therefore of the work-output of the processes of developing, maintaining
and enhancing a software product).
2 ÓISO/IEC 2002 – All rights reserved

In terms of the sizes produced, the major differences are that Mk II FPA, with its finer
granularity, is a continuous measure whereas IFPUG limits component size once a
threshold is reached and that the MkII method aims to better reflect the internal
processing complexity of business ‘data-rich’ systems.  As the concepts on which
the size measure is based are logical transactions and entities, in which software
requirements and functional specifications are typically expressed, a MkII Functional
Size measure should be truly independent of the technology or methods used to
develop or implement the software.
The weightings introduced by Charles Symons were designed to deliver a size scale
of similar magnitude for the MkII method as for the IFPUG method. On average
therefore, the methods give roughly the same software sizes up to around 400
function points (though there can be quite a scatter about the average for individual
items of software). For larger sizes, Mk II FPA tends to produce increasingly higher
sizes than the Albrecht/IFPUG method.
For some purposes, e.g. portfolio management, the methods may be regarded as
equivalent. However, for the commonest purposes of performance measurement
and estimating it is preferable to use one scale or the other consistently, only
converting between them if needed, using a formula which shows the average
relationship.
1.5 Applicability of Mk II FPA
MkII FPA is a method that assists in measuring process efficiency and managing
costs for application software development, enhancement or maintenance activities.
It measures a software product size independent of technical characteristics of the
software, in terms relevant to users. It can be:
· applied early in the software development process
· applied uniformly throughout the software's lifetime
· interpreted in business terms, and
· understood by users of the software.
MkII Function Points can be used to measure the functional size of any software
application that can be described in terms of logical transactions, each comprising an
input, process and output component.  The sizing rules were designed to apply to
application software from the domain of business information systems, where the
processing component of each transaction tends to be dominated by considerations
of the storage or retrieval of data. The method may be applicable to software from
other domains, but the user should note that the sizing rules do not take into account
contributions to size such as from complex algorithms as typically found in scientific
and engineering software, nor do the rules specifically take into account real-time
requirements. To apply MkII FPA to these other domains may be possible or may
require extensions to or new interpretations of the rules given in this manual.
MkII FPA can be used for sizing:
· a requirements specification or functional specification of a new
application or of a change to an existing application
· the requirements met by an existing, operational application,
whether it be a bespoke application or an implementation of a
packaged business software solution, and whether a batch or on-
line implementation.
ÓISO/IEC 2002 – All rights reserved 3

Either directly, or coupled with effort, defect counts and other measures, MkII FPA can
be used for a variety of purposes, including to:
· measure project or organisational performance (productivity,
delivery rate and quality).
· compare internal and external IT performance
· compare application quality and reliability
· compare normalised development, maintenance and support costs
of applications on different platforms
· estimate the resourcing requirements, duration and cost of projects
· contribute to t
...