Software Engineering | How effort distribution is done?

  Each of the software project estimation techniques leads to estimates of work units (e.g., person-months) required to complete software development.  

 A recommended distribution of effort across the software process is often referred to as the 40–20–40 rule. Forty percent of all effort is allocated to front end analysis and design. A similar percentage is applied to back-end testing and coding (20 percent of effort) is de emphasized.  

 This effort distribution should be used as a guideline only. 

 The characteristics of each project dictate the distribution of effort. Work expended on project planning rarely accounts for more than 2 to 3 percent of effort, unless the plan commits an organization to large expenditures with high risk.  

 Customer communication and requirements analysis may comprise 10 to 25 percent of project effort. Effort expended on analysis or prototyping should increase in direct proportion with project size and complexity.  

 A range of 20 to 25 percent of effort is normally applied to software design. Time expended for design review and subsequent iteration must also be considered. 

 Because of the effort applied to software design, code should follow with relatively little difficulty.  

 A range of 15 to 20 percent of overall effort can be achieved. Testing and subsequent debugging can account for 30 to 40 percent of software development effort.  

 The criticality of the software often dictates the amount of testing that is required.