Back to Monte Carlo
02 - Risk how-to

How to use Monte Carlo

Use this guide to operate the native Monte Carlo module: the risk register, uncertainty bands, simulation results, driver analysis, and the cross-update burn-down.

Quick Start

  1. Open a project and go to its Monte Carlo module.
  2. Add risk events in the Risk Register tab, and duration bands in Uncertainty Bands.
  3. Run the simulation.
  4. Review Results, Drivers, and Burn-down, and check the Calculation Glossary for methodology.
01

Risk Register

  1. Click Add Risk to create a discrete risk event.
  2. Set its probability percent and a min/likely/max day impact and cost impact (sampled from a triangular distribution).
  3. Use Targets to pick which activities the risk applies to, or leave it as "Whole project (serial)" to extend the finish directly.
  4. Set a Correlation group (e.g. "weather") so multiple risks that should occur together share one occurrence draw per simulation run.
  5. Save or load a named register to reuse a risk set across runs.
02

Uncertainty Bands

  1. Set the default Min/Likely/Max percent range applied to every activity's remaining duration (before any risk events are added).
  2. Add an override for a specific activity code (format "Type:Value", e.g. "Phase:Construction") when part of the schedule needs a different band.
  3. Completed work and milestones are not resampled.
03

Run the simulation

  1. Confirm the risk register and uncertainty bands are ready, then run the simulation.
  2. The engine runs a full CPM-per-iteration simulation over the parsed activity network (up to 10,000 iterations), calendar-aware, deterministic by default so identical inputs reproduce identical results.
  3. Re-run after editing risks or bands to see updated results.
04

Use Results

  1. Open the Results tab after a run completes.
  2. Read the Finish Date Risk Curve for how many days beyond the deterministic finish each percentile lands.
  3. Check the Milestone Forecast table for each milestone's deterministic, P50, and P80 dates.
05

Use Drivers

  1. Open the Drivers tab.
  2. Read the tornado chart for which risks and activities most affect total duration.
  3. Check the Criticality Index table for the percent of iterations each activity sat on the driving path.
06

Use Burn-down and the Glossary

  1. Open Burn-down to see the P50/P80 finish trend across schedule updates, once the project has more than one run.
  2. Open Calculation Glossary for the exact formula behind every metric on this page.
Module overview