Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Critical path DRAG (Devaux’s Removed Activity Gauge) is a new scheduling metric in critical path analysis [http://planningplanet.com/wiki/index.php?q=35/critical-path-method].  It is the amount of time that an activity on the critical path [http://planningplanet.com/wiki/index.php?q=220/critical-path] (i.e., the longest path through the project) is adding to the project’s duration or, alternatively, the amount of time by which the project completion would be pulled in by reducing a critical path activity’s [http://planningplanet.com/wiki/index.php?q=219/critical-activity] duration to zero. 

Activities that are not on the critical path are said to have total float [http://planningplanet.com/wiki/index.php?q=37/total-float] or slack, i.e., the amount of time they can slip without making the project longer.  Conversely, only critical path activities and delays (such as lags or constraints [http://planningplanet.com/wiki/index.php?q=28/constraint]) have DRAG.   

1. DRAG can be computed in the following manner:
2. If an activity has nothing in parallel, its DRAG is equal to its duration.

If an activity has other paths in parallel, its DRAG is whichever is less: its duration or the total float of the parallel activity with the least total float.

There are three commercially avaliable software packages that compute DRAG:

• Spider Project.
• PlanontheNet.com
• Sumatra.com's Project Optimizer, which ias an add-on to Microsoft Project.

DRAG has a corollary cost effect called DRAG Cost [http://planningplanet.com/wiki/index.php?q=35/DRAG-Cost], which is the amount by which project profit is decreased due to an activity’s DRAG reducing the value of the deliverable and/or increasing project cost through indirect costs attached to level-of-effort activities or overhead.