|Expression||MDX expression that typically returns a measure, a tuple, or a string.|
A report has a measure that should calculate one common value and then reuse it for different other formulas. For example, the report calculates a start date of the report and then uses this start date for different cases - to show periods, calculate predictions, etc.
The formula example below calculates the start date of the report based on the individual version start date or the first date when an issue was moved to in progress. This calculation will be applied only once (first context) per report execution. It should be used in other calculations to get value out of caching those results.