In reply to ChristopherLockley:
Just a quick note to provide some additional guidance ... As many have mentioned in the comments, the question regarding highest achieved grade is not appropriate to non-boulderers! If this applies to you, please just write your highest grade in the appropriate grading system.
Additionally, there's a good number of "live" participants, i.e., people that have started the questionnaire but haven't submitted it. While I'm sure a number of these are people that haven't completed the questionnaire for whatever reason, I just want to point out that when you're presented with the page that says "Thank you", your responses are not logged until you click next. It's a little misleading, so I apologise for that. I would probably exit the browser at that point, so thought it was worth a note just in case you're like me!
Thanks again, everyone.