The Top Activities Report provides insight into the most popular activities. It shows the count of activities, the total time earned completing the activity (estimated time to complete), and the number of times the activity was completed. It's a great report for seeing the most popular (and least popular) activities within your games.
There are several filters that allow you to drill down to specific districts, games, levels, and missions. You can also specify a start and end date range that selects when activities were approved. For example, you can see activities that were popular over the past month by setting this date range.