Introducing Calculation Groups
Calculation groups are a new feature in DAX, inspired from a similar feature available in MDX known as calculated members. Calculation groups are easy to use; however, designing a model with calculation groups correctly can be challenging when you create multiple calculation groups or when you use calculation items in measures.
Before we provide a description of calculation groups, it is useful to spend some time analyzing the business requirement that led to the introduction of this feature. An example involving time-related calculations fits perfectly well.