1. Check if it is the number of users or likes per users that are increased year over year. If it is the total number of users that increased by 10% or so, then that could be the reason you have the increase in the likes. If it’s not the number of users (or if the growth in the user is not quite close to 10%) then check the following two things.
1-1. Check if there has been a feature update that made it easier and more convenient for the users to click “like” (e.g., change in the size of font/icon as well as its location and etc). If so there could be another feature that could have been de-prioritized due to this change. Check what other impacts it could have caused due to the increase in the likes.
1-2. Check if there has been events that might be the drivers (e.g., number of events, news, posts/shares associated with the news)
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