Use Case Points

An approach to estimating and planning with use cases:

• Complicated use cases generally take longer to code than simple use cases
• By assigning points to use cases we can use this to measure the size of the application and derive an expected duration for the project using the team's rate of progress
• Points are assigned by weighing the complexity of the use cases and actors and then adjusting their combined weight to reflect the influence of the nonfunctional and environmental factors
  

The number of use case points in a project is a function of the following:

• the number and complexity of the use cases in the system
• the number and complexity of the actors on the system
• various non-functional requirements (such as portability, performance, maintainability) that are not written as use cases
• the environment in which the project will be developed (such as the language, the team’s motivation, and so on)

See: Estimating with Use Case Points