We didn't start charging until we had been live for about 10 months, this is where it went from a cool side project to realising that we had something here. Once we started charging we were making a tiny amount of money straight away because we already had a lot of users.

A lot of people do run their own versions, these are generally universities who do not want their data going to 3rd parties. Its impossible for us to get exact numbers on it though.

We were worried about other people stealing our code, some other people do run our site however your self hosted version is always going to be best, it will have all the SEO, more users, get the updates quickest.

Most of our income is via self hosted.