Function Points in the Lifecycle

1. Function Points in the Lifecycle • Function point measure’s categories. • Productivity • Quality • Financial • Maintenance

2. CHAPTER 3 (Garmus – Herron) MEASURING WITH FUNCTION POINTS

3. Productivity’s Measurement • Hours per function point • It measures the number of hours required to develop one function point. • Calculate as followed: • Total # of project hrs / # of function point delivered • Information technology productivity • Is the overall productivity of the IT department • Calculate as followed: • Total function points / Total IT work effort • Delivered functionality & Development functionality • Indicate how much functionality was actually delivered to the end user in relation to the rate of productivity of the developed functionality. • Calculate as followed: • Total cost / Total functionality delivered • Total development effort hours / Total functionality developed in-house

4. Quality’s Measurement • Functional requirement size • Measures the total number of functions requested by end user expressed in terms of function points • The calculation derives the function points required by a requesting user organization • Completeness • Measures the functionality delivered versus the functionality originally requested. • Rate of change • Measure calendar time to deliver the required software solution to end user. • Calculate as followed: • # of function point / Elapsed calendar time

5. Quality’s Measurement • Defect removal efficiency • Total # of defects found prior to delivery / Total # of defects • Defect density • Measures the number of defects identified across one or more phases of the development project life cycle and compare that value to the total size of application • # of defects / Total # of function points • Test case coverage • Measure number of test cases that are necessary to adequately support thorough testing of a development project. • # of test cases / Total # of function points • Volume of documentation • Measure or estimate the number of pages produced or anticipated in support of the development effort • # of pages / Total # of function points

6. Financial Measurement • Cost per function point • Identifies the cost for each function point developed • Total cost / Total function points • Repair cost ratio • Used to track the costs to repair applications that are operational. It common used as a monitoring metric for newly installed applications • (Total hrs to repair * Cost per hrs) / Release function point

7. Maintenance’s Measurement • Maintainability • Measures cost required to maintain an application • Maintenance cost / Application function points • Reliability • Measure the number of failures an application experience relative to its function size • # of production failures / Total application function point • Assignment scope • Measure the number of FTE resources required to support an application • Total application function points / Number of fulltime resources required to support the application

8. Maintenance’s Measurement • Rate of growth • Measure the growth of an application’s functionality over the specific period of time. • Current # of function points / Original number of function point • Portfolio size • Measure the organization’s portfolio of function points • Use for budgeting purposes or in conjunction with out-sourcing arrangement • Backfire value • Number of lines of code factored by a language complexity multiplier to derive the number of function points. • Stability ratio • Used to monitor how effectively an application or enhancement has met the expectations of the user (base on the number of changes that were required during the first 60 to 90 days of production.) • # of changes / # of application function points

9. Use of Function Point Measures in the System Development Lifecycle

10. Use of Function Point Measures in the System Development Lifecycle

11. Use of Function Point Measures in the System Development Lifecycle

12. Using Function Point Measurement Data Effectively • The key ingredients to a successful measurement program include the following: • Establishing a metrics repository that is centrally located and secured • A well-defined set of measures that are properly documented • The ability to effectively report the results and properly analyze the metrics data

13. Developing a Measurement Profile • A metrics profile should be developed for each measure. • Is an efficient ways to communicate critical information about the measure • To promote consistent use of the measure • For Example:

14. Example: Measurement Profile Metrics: Cost per function point Purpose: To measure cost for application development and enhancements Definitions:Cost is the total of labor hours, regular and overtime charged to the project by all team members. Size is the number of function points delivered on a project. Data Element Required: Project hours Size of project in function points Formula: Hours will be used only as the cost basic to report projects that required less than three effort months. Description of Collection Procedure: Labor hours are reported on a weekly basis. Function points are counted at acceptance, upon scope changes, and at delivery. Frequency of Collection: Project delivery Commencement date: Reporting of data will begin July 1, 2000