This paper was originally authored by Greg Gendall of Midori Media and published by Project Magazine in May 2003.
It has since been revised and updated by the present author.
It was submitted for publication by Email, February 16, 2009, and is copyright © David Garland.
Published here May 2009.
What is an S-curve?
An S-curve is defined as:
"A display of cumulative costs, labor hours or other quantities plotted against time. The name derives from the S-like shape of the curve, flatter at the beginning and end and steeper in the middle, which is typical of most projects. The beginning represents a slow, deliberate but accelerating start, while the end represents a deceleration as the work runs out."
Types of S-curves
There are a variety of S-curves that are applicable to project management applications, including:
- Man Hours versus Time S-curve
- Costs versus Time S-curve
- Baseline S-curve
- Actual S-curve
- Target S-curve
- Value and Percentage S-curves
Each of these is described in the following pages.
1. Source: Wideman Comparative Glossary of Common Project Management Terms v2.1 Copyright R. Max Wideman, May 2001