To implement a calculation item for month-to-date change, which DAX function should be used as part of the expression?

The use of the CALCULATE function is crucial when implementing a calculation item for month-to-date change in DAX (Data Analysis Expressions). CALCULATE allows you to modify the context in which data is evaluated, making it essential for performing calculations that require context transition or filtering data based on specific criteria.

When calculating month-to-date changes, the CALCULATE function can be paired with time intelligence functions, such as TOTALMTD, to filter the data to only include the current month up to the current date. This ensures that the calculation reflects only the relevant period, allowing for accurate month-to-date analysis. The ability to adjust filters not only enhances the flexibility of your calculations but also enables more sophisticated data analysis, tailored to specific time dimensions.

Other functions mentioned serve different purposes. GENERATE, for example, is used for creating a row context from an existing table, while MEASURE refers to a specific type of calculation in Power BI but does not imply any specific calculation logic. COMBINEVALUES is used for concatenating values into a single string and does not directly pertain to the context of calculating month-to-date changes. Thus, CALCULATE stands out as the necessary function for this scenario.