Does "user" mean "distinct human" or "user account" in this context? Need to keep in mind the culture of throwaways. If 10% of users make a throwaway at a rate

Does "user" mean "distinct human" or "user account" in this context? Need to keep in mind the culture of throwaways. If 10% of users make a throwaway at a rate of 5 per month, then 100 monthly humans == 150 monthly usernames.