A calculation group is an element of the semantic model that can replace a measure expression with the DAX formula of a calculation item.
DAX Optimizer does not evaluate the cost of calculation items and calculation groups when analyzing the performance of DAX measures.
As a result, metrics such as relevance, impact, and execution counts are not provided for calculation groups. Instead, only identified issues are reported.
Workaround for calculation groups
As a workaround, create a measure that expands the DAX expression of a calculation item applied to another expensive measure so you can figure out the cost of the calculation item by evaluating the difference between the original and the modified measure. Read more in Analyzing calculation groups.
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