Information Based Schedule: Schedule Forecasts and Supporting Data

PMBOK v8 Definition

An Information Based Schedule includes items such as resource histograms, cash flow projections, order and delivery schedules, or other relevant information. Schedule forecasts are estimates or predictions of conditions and events in the project’s future based on information and knowledge available at the time the schedule is calculated. Forecasts are updated and reissued based on work performance information provided as the project is executed, relying on the project’s past performance and its expected future performance based on corrective or preventive actions.

This concept is part of the Project Schedule Management knowledge area, specifically within the Monitor and Control Schedule process and the Develop Schedule process.

Why It Matters for the Exam

The PMI exam frequently tests your understanding of what constitutes schedule data versus schedule forecasts. Questions appear in situational scenarios where you must identify which documents are part of an information-based schedule, and when forecasts should be updated based on performance data. Expect 2-3 questions on this topic, often asking you to distinguish between supporting detail and actual schedule components.

Key Points to Remember (for the exam)

Core Definition: Schedule forecasts are estimates/predictions of future project conditions and events, based on information available at the time the schedule is calculated
Update Trigger: Forecasts are updated and reissued based on work performance information provided during project execution
Basis of Forecasts: Information is based on the project’s past performance AND expected future performance considering corrective or preventive actions
Supporting Detail Components:
- Resource requirements by time period (resource histogram)
- Alternative schedules (best case, worst case, resource-leveled, not-resource-leveled)
- Applied schedule reserves
- Cash flow projections
- Order and delivery schedules
Minimum Schedule Components: Schedule milestones, schedule activities, activity attributes, and documentation of all identified assumptions and constraints
Common Confusion: Schedule data includes supporting detail (histograms, cash flows) while schedule forecasts are predictions based on that data—they are related but distinct

Typical PMI Exam Example

A project manager is reviewing the project schedule and notices that resource histograms show a conflict during weeks 4-6. The project sponsor asks for updated delivery timelines. What should the project manager use to predict future schedule performance? Answer: Schedule forecasts, which are based on current work performance information and past performance data, updated with corrective actions.

PMI Exam Traps

Trap: Confusing schedule data with schedule forecasts Reality: Schedule data includes supporting detail (resource histograms, cash flows) while schedule forecasts are predictions of future conditions based on that data
Trap: Thinking forecasts are only based on past performance Reality: Forecasts are based on past performance AND expected future performance considering corrective or preventive actions
Trap: Assuming schedule forecasts are static once created Reality: Forecasts are updated and reissued based on work performance information as the project is executed
Trap: Confusing "schedule forecasts" with "schedule baseline" Reality: The schedule baseline is the approved version; schedule forecasts are dynamic predictions updated throughout the project

Important PMI Connections

Related Concept	Relationship Type	Exam Attention Point
Develop Schedule	Process that creates the schedule model	Schedule forecasts are outputs updated during this process; forecasts require analyzing sequences, durations, and resource requirements
Monitor and Control Schedule	Process that updates forecasts	This process monitors status, updates the schedule, and manages changes—forecasts are key inputs for this work
Work Performance Information	Input to forecast updates	Forecasts are updated based on work performance information provided during execution
Schedule Management Plan	Establishes policies for schedule	Plan Schedule Management defines how forecasts and schedule data are documented and maintained
Schedule Data	Supporting detail for forecasts	Includes resource histograms, cash flow projections, order/delivery schedules—all part of the information-based schedule

Quick Review Questions

What are schedule forecasts based on, according to PMBOK v8?
Name at least three types of information that can be included in an information-based schedule as supporting detail.
When should schedule forecasts be updated and reissued?
What is the difference between schedule data and schedule forecasts?
What are the minimum components that a schedule must include?

PMBOK v8 Reference

Section 2.3.2.1 – Plan Schedule Management (pages 49-53) Section 2 – Project Management Performance Domains Processes: Develop Schedule, Monitor and Control Schedule