Calculation groups provide a simple way to reduce the number of measures in a model by grouping common measure expressions. Calculation groups work with existing explicit DAX measures by automating repetitive patterns. For example, a sales analyst might want to view sales and order quantities by month-to-date (MTD), quarter-to-date (QTD), year-to-date (YTD), orders year-to-date for the previous year (PY), and so on. With this enhancement, data modelers will be able to create calculation groups by using Power BI Desktop.