Project Durations and Contingencies

Blog. Comments Off on Project Durations and Contingencies

Predicting project completion times is one of the challenges of Project Managers. Project schedule overruns are quite common due to uncertainty in estimating task durations, lack of historical data, inadequate skill, etc.

We could simply add the usual 10% schedule contingency to help ensure we finish our project on time or maybe we could take a more scientific approach based on a beta (β) frequency distribution and the PERT (programme evaluation and review technique) formula:

In this situation, the project critical path BET = (O + 4ML + P)/6 = (22 + 160 + 100) = 47 days, the Standard Deviation = (P – O)/6 = 13 days, and Contingency = Standard Factor x Standard Deviation. The Standard Factor is the same for all projects. As with all estimates, their accuracy depends on the accuracy of the input data. To … Read More »


My latest thoughts on Project Management and life.

Business Analyst (BA) and Analysis

To survive or preferably thrive, organisations cannot stand still. They must evolve and progress to remain alive. Such evolution and progress requires projects. And...

Free Book: “Managing Smaller and Medium-Sized Projects” by Dr Jim Young PMP

I acknowledge with sincere appreciation the contributions to this book from numerous clients, student, colleagues, friends and project management practitioners. Their sometimes unwitting input...

The “Lean” Project

Lean is an often-used adjective in business these days, but there’s some confusion over its exact definition. In essence, the goal of Lean is...