There may be a very large group of users who listen less than an hour per month. In other words, their population of users may include people who signed up, but rarely use it and could stretch the definition of what would be considered active users.

Are you a paying user? I use pandora a lot but I have a subscription $3/mo is nothing. I probably listen 5+ hours at work to suppress the sound of people talking around me.

It's only for mobile usage. Web usage is uncapped.

Probably 4% of all users, not active users. I listen to significantly less than 40/h per month because I almost never log on.