Hi,
I have created a User Access report for CRM on-premise using SQl query in the following format. One row corresponds to one user in organization. Currently, I am using Microsoft Dynamics CRM Online trial version and have two users in my organization.

I want to the same report for CRM Online environment. Only Fetch-Xml based custom reports are supported by CRM online environment hence this SQL query cannot be used.
I have already written fetch-xml query to retrieve user access records ("audit" entity records) in "last-x-months" (where x = 1,2,3,4,5,6) as below.

I am able to retrieve the records with "last-x-months" condition at a time, for example, the last-2-months in my fetch-xml query only.
For, example, when I retrieve the records in the last-2-months, it also includes the records in the last month. I want to count the records in the 2nd month only that is the difference between these two. The difference will be my 2nd column.
Similarly, I want the other columns.
For the case in the above example, I have created the two separate datasets to get the record-count for the last month and last-2-months. But, I am not able to use the two datasets in the same table in my report and hence not able to calculate the difference.
Is there any way to solve this problem?