What is the backwards compatible switch when creating a new project ?

When creating a project you may choose two ways to perform certain calculations: N&L way and the legacy way that software like P6 uses. 

If you want your results to be like P6's results leave this ON. 

What does this switch affect. 

• Activities taken into account when calculating float:
  • OFF: Both completed and non-completed activities are taken into account. 
  • ON: Only completed activities are taken into account. 
• Contrains taken into account when computing float: 
  • OFF: Constrains are not taken into account when computing total float. 
  • ON: Contrains are taking into account when compiting total float. 
• Schedule compression: 
  • OFF: We define the free float as the maximum amount of time that an activity can be delayed without delaying a successor. We sum the values. 
  • ON: We sum the free float exactly like P6.