How are function points used?
Function points are used in three ways: • As a measure of software assets or activities. For example, the number of function points under maintenance, the number of defects per function point developed, the development cost per function point, or the maintenance cost per function point. • To estimate effort. Using databases of completed projects, researchers have published formulas that translate function points into effort measured in man-hours. Hence, if you know the number of function points that need to be developed, and the formula is accurate, you have a method for estimating the development effort. • To measure productivity. Because function points measure the amount of functionality it an application contains, the number of function points divided by the amount of effort in man-hours to build the application can serve as a measure of productivity. However, there are situations when legitimate effort is applied without a commensurate increase in the function point count (indeed,
