What is a Banana Curve in Project Management?

A banana curve is a form of an s-curve and used in project management. These days all project management software or project scheduling software has facilities to provide the banana curve with a few clicks.

While developing the project network diagram, you identify each activity’s early start, early finish, late start, and late finish. These data help you find a total float, free float, critical path, near critical path, etc.

You can have two s-curves with this information: the first s-curve uses early start dates, and the second uses late start dates.

The early start dates show the early dates the activities and the project can start.

The late start dates show the latest dates the activities and the project can start.

Likewise, the late start and late finish dates show how late the activities or projects can start and finish.

Now you can have two s-curves. 

The first s-curve uses the early start and early finish dates, called early s-curve.

The second s-curve uses the late start and finish dates called the late s-curve. 

Now, when you plot both curves on a graph, the beginning and end of project curves overlap and form the shape of a banana, which is why this curve is known as the “banana curve.”

If you enter the actual data in the graph, the progress line will be between the two s-curves.

The banana curve helps find flexibility in the project schedule. However, if the actual progress is nearing the late s-curve, the project has a risk of being delayed.

Summary

A banana curve is a form of an s-curve, where you superimpose a late s-curve and an early s-curve. The shape of this curve is like a banana, which is why they call the curve the banana curve.