PM tip

Using the PERT Analysis Tool in MS Project 2000 Can Dramatically Improve Schedule Accuracy

Project management tip  ·  Microsoft Project 2000

A PERT chart showing project activities, dependencies and the critical path
PERT charts make task dependencies and the critical path visible at a glance.

For years MS Project misused the acronym PERT. With MS Project 2000 that has changed, and project managers now have a powerful new tool to assist in developing accurate timelines. PERT — Program Evaluation and Review Technique — makes use of three duration estimates for each item in the project plan: the worst case, the most likely and the best case. These three numbers are combined to create a weighted average.

The calculation emphasizes the most likely estimate, but it tends to increase the overall estimated time an activity or task will take compared to the standard expert opinion we most often use — which is exactly why it produces more honest, more accurate schedules.

How to use it

  1. Go to the View menu, then Toolbars, and select the PERT Analysis toolbar.
  2. On the task you want to address, open the PERT form and enter the optimistic, pessimistic and most likely durations.
  3. Project keeps all three estimates in separate columns, so you can view the overall estimate based on any of the three numbers.
  4. When you are ready, select the Calculate PERT button (it looks like a calculator) to create the weighted average estimated time.

Using this technique will dramatically improve the accuracy of your schedules. Want to go deeper? Our MS Project 2000 Basics and MS Project 2000 Advanced courses cover scheduling and estimating techniques hands-on, and Simulation Modeling for Project Management takes duration estimating to the next level with Monte Carlo simulation.