Use the line view in Explore to build a retention query that will use the nested event property built in question 46. This should show day 0 for all users and the % of those users that return each day since their first day, for every day into the future. This should be run from the beginning of time to now.
Build a retention query in Explore that uses line view, this query should return the rate of retention for users relative to their daily return rate. This query will use one measure that returns a count of unique user actors filtered to all user actors and is split by the actor property created in question 46. Measure 1 should also include "as a fraction of..." all. Run the query from the beginning of time to now.
Retention is the foundation for some of the most powerful and valuable queries you can construct in Scuba. As we learned when creating the actor property from question 46, we can assign a day number to each day, we can determine a users first day number and then by subtracting the two we can see how many days it has been since a users first day. In this query, every user has a day 0, which is their first day, but every users day 0 does not have to be the same calendar day. Day 1 that we see in the returned results is 1 day since the users first day, day 2 is 2 days since the users first day and so on. This query is simply counting if a user had generated an event on a given day number since their first day and if they did they are considered retained. So when we see that 100% of users have a day 0 that is because every user has to have a first day at some point in time, and when we see that 27% of users have a day 1, that's because 27% of users return 1 day after their first day.
Note: The numbers and result do 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*