Documenting Assumptions
Well-documented assumptions are the foundation of a credible forecast. Each overlay in Galdera represents one assumption — and its canvas is the right place to capture everything a reviewer needs to evaluate that assumption.
Best practices for documenting overlay assumptions:
- Be specific about the source: "Based on signed contract" is stronger than "Based on sales estimate"
- State the key dependencies: "This assumes the product launches in Q3 as scheduled"
- Note the review trigger: "Revisit if churn rate exceeds 8% in Q2"
- Capture the date of the assumption: Business conditions change; knowing when the assumption was made matters
The canvas documentation on a Forecast Version records what was believed at the time of the forecast, creating an auditable trail that boards and auditors can review. Keep past versions' canvases untouched once a planning cycle closes so that record stays meaningful.