The plot shows the time series of the total number of users in Mastodon as a function of time since Sept 1st. It starts around 5.2 million users and stays below 5.7 until Nov 4th, when Musk completed the purchase of Twitter. Then it began to grow faster and today (Nov 14th) the total number of users is around 6.7 Million users. Since Nov 4th, 860k new users were registered at a mastodon instance
https://files.mastodon.social/media_attachments/files/109/342/652/002/689/316/original/1e97512c57e96856.png