I mean to list all chronologically all activity on your resumé including self-employment, consulting, speaking, writing etc. from which you derived income in the past ten years...I don't even remember what I had for breakfast last week.
That questionnaire may be a tough cookie but I think it is pretty helpful to sort the good from the bad. After all let's not forget that the successful candidates will be running one of the world's greatest nations. They better be honest and trustworthy.
This actually brings me to a question that. What's the weirdest thing you had to provide to your current/future employer? I had to provide a letter from the Ministry of Justice that I haven't been previously convicted and am not a convicted felon. Phew.