Build a query in Explore that will return a count of users that is filtered to all user actors and is starting at 7 days ago and ending now. Use the compare to option below starting and ending time that uses the offset of 7 days before. Use number view to visualize the result.
Note: The numbers and result does not need to be an exact match as the data changes over time. The query construction is what is most important. See images below.
*Click to enlarge*