Advantages / Benefits of Function Point Analysis

Function Point Analysis is seen as a significantly important took / process for doing estimation. But what exactly are the benefits that you can get via this process, and why is this something that people are willing to pay good money to learn ? Reading ahead, you will see reasons outlined (and if you are willing to share your own story of how FPA worked for you, please share via the comments).

Function Point Analysis lets you have the ability to do a reasonably accurate estimate of the most important estimation metric:
- The project cost
- The duration of the project
- The number of resources required to staff the project

In addition, there are more metrics that are required for a project, and FPA helps in understanding them much better:
- You can get a good idea of the project defect rate
- By calculating the number of Function Points (FP's), you can calculate the cost per FP
- Similar calculations will get you the FP's per hour
- If you are experimenting with using new tools, using FP's provides you an easy way to determine the productivity benefits of using new or different tools

Some of the other benefits of using Function Point Analysis are listed below:
- By measuring FP's, you can guard against increase in scope (function creep)
- Measurement of performance indicators enables benchmarking against other teams and projects
- Project Scoping: By breaking the project into several small functions, you get the advantage of being able to easily convey the scope of the application to the user
measured in function points.
- Assessing Replacement Impact: If existing applications have to be replaced by a similar application, you know the desired FP (and the size of current project).
- Assessing Replacement Cost: Once you know the replacement impact, it is easier to derive the replacement cost, since some standard figures are available for cost per FP
- Testing Resources: With the help of the FP's calculated during the project, it is easier to calculate the areas that are more complex and will require more testing effort.

In summary, Function points work well as a measurement tool in part because, they are relatively small units and can be measured easily. These measurements in turn can be used to derive a number of project related metrics.