Are there any open-source datasets available for studying user engagement trends over time?

 Yes, there are several open-source datasets available for studying user engagement trends over time. Here are a few examples:

1. The Google Analytics Sample dataset is a public dataset that includes website engagement data for a retail company. The dataset includes information on sessions, users, pageviews, and bounce rate, and can be used to study user engagement trends over time.
2. The Reddit comments dataset is a collection of 1.7 billion comments from the social media platform Reddit. The dataset includes information on user engagement, such as the number of comments and upvotes, and can be used to study engagement trends over time.
3. The Stack Overflow dataset is a collection of data from the popular Q&A platform for programmers. The dataset includes information on user engagement, such as the number of questions and answers, and can be used to study engagement trends over time.
4. The Wikipedia Edits dataset is a collection of data on Wikipedia edits, it includes information on user engagement such as the number of edits, and can be used to study engagement trends over time.
5. The Tweet dataset is a collection of tweets from Twitter, it includes information on user engagement such as the number of likes, retweets, and comments and can be used to study engagement trends over time.

These are just a few examples of the open-source datasets available for studying user engagement trends over time, there may be more datasets that are specific to certain domains or platforms, and it would be helpful to do more thorough research on the available datasets.