I think, the survey can not count the number of users bitcoin. Because we know the surveys are boring thing and some people if meets survey they would tend to avoid it. And I think the survey is not an appropriate thing to know about it.
These surveys wouldn't be successful because people wouldn't do effort to participate. Would it be beneficial to them? No. Unless this survey would beneficial or they're forced to take this survey, they wouldn't take it.
I think the number of users bitcoin could never be calculated precisely, if bitcoin itself still can not be accepted by the government. because help government with data collection, the number of users bitcoin can be done.
Thank you
I don't think that's likely to happen because of the very reason the government don't care about bitcoins. Maybe it's on their list of things that might affect them in the far future, but right now, they don't plan on accepting it or even recognizing it. There's no reason for them to help us with data collection even if they start accepting bitcoins.