Data 360: Workaround for using Group By functionality in Data 360 Reports

At this time, there is a limitation on changing "the granularity level on grouped date fields" as noted in our documentation here: Data 360 Reports and Dashboards: Limits and Limitations 

A workaround you can use is to create a row-level formula on the datetime field to convert it to a date data type. This will generate an additional column in your report to display the output values. From there, the new column can be grouped by month, quarter, year, etc. This works inversely as well for converting date fields to datetime data type. 

Please note that each Data 360 report supports only one row-level formula.