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Risk - a Risk is represented by a Jira issue of a predefined Jira issue type. Risk properties like probability and impact are Jira custom fields assigned to the Risk issue type via issue screens. You can define more than one risk issue type for Risks if needed. For instance, you could have one risk issue type for opportunities (positive risks) and one for threats (negative risks)issue type per risk kind, like Financial risk, Operational risk, etc.

Measure - a Measure is represented by a Jira issue of a predefined Jira issue type. A Measure is associated with a Risk via an issue link of a predefined issue link type. Like risks, you can define more than one measure issue type.

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Risk Formulas - A mathematical expression that sets the value of a numerical field based on one or more numerical fields on the same issue.

Administration Guide