CALCULATE is one of the most commonly used functions in DAX. It is used to calculate expressions, usually given by some aggregation function, with use of one or more filters. It is not incorrect to use CALCULATE without a filter, but that’s not much point. The strength of this function is the ability of combining expression with a range of DAX functions that narrow set of data to perform aggregation with…
Aggregation of data is a process that we’re implicitly performing every time we drag a reporting dimension in the field Values. However, when you create complex reports, it is useful to use functions for aggregation (SUM, AVERAGE, COUNT) to create measures that will be used in the report. Once thought out measures may be used as a building block to create complex DAX expressions.
When making extensive reports, there is often a need to calculate subtotals by reporting categories. Subtotals are, most of the time, sums and they might also be an average, a minimum, a maximum, a product, or a count of articles within a report. Subtotals can be made manually and in this „recipe“ it will be about how to use Excel for automatically adding subtotals.
Aggregation is a term that signifies unification and calculation. It combines one or more data sets, which are given as function arguments, for performing a mathematical operation. This may be: summing up a series of data, counting, averaging, calculating the minimum or maximum value of a given set of numbers… Aggregate functions are very commonly used and should know them well.