100 Percent Rule

100 percent rule is the most important criterion in developing and evaluating the WBS. The rule states: “The next level decomposition of a WBS element (child level) must represent 100 percent of the work applicable to the next higher (parent) element.” (17) In other words, if each level of the WBS follows the 100 percent rule down to the activities, then we are confident that 100 percent of the activities will have been identified when we develop the project schedule. Moreover, 100 percent of the costs or resources required will be identified when we create the budget for our project.