The PM window can be used to add and edit progress information to a project. When progress information is added, the Schedule data set contains all the progress variables; see Progress Updating.
However, all the values of the progress variables are reconciled and revised on the basis of the value of the TIMENOW parameter. Since the PM procedure enables you to move the TIMENOW line as well as implicitly change the value of TIMENOW by updating the Actual Start or Finish times of the activities, the value of TIMENOW at the end of the editing session is an important parameter of the project. This value is saved in a macro variable called TIMENOW and can be used in subsequent editing sessions of the same project. See Example 5.6 for an example of the use of the TIMENOW macro variable.