Kasper de Jonge walks us through calculation groups:
In most cases the business wants to see some common calculations done over these measures like YTD, QTD, YoY% etc. That means you must make a new measure for each of the calculation over the base measure. This leads to measure explosion in your model as you need to add a new measure for each variation. Very quickly this leads to not four measures but sixteen and more creating a management headache.
In come calculation groups. With calculation groups you can create a group that can apply common calculation over base measures. It’s hard to explain so let’s just dive in on how that works.
Click through for a demo of how to enable and use calculation groups.