Your survey was interesting, but I don't feel that it applied to me accurately. The only data losses that I have had were due to human error (i.e. I deleted something by mistake), not computer error. Also, I am a cheapskate and would rather continue using my current backup methods for free rather than pay for the conveinience of some sort of backup service. (yes, I cook at home...yes, I do my own oil changes...cheap,cheap,cheap)
In the "have you ever lost data that was irretrievable" section you should add a "yes, but only because I accidentally deleted it" option.
Or, have the next question be "what caused your data loss?" & then have a choice between "A computer malfunction" or "I deleted it by mistake".
You could also add an "I would not be interested" option for the last question.
I think adding these would improve the accuracy of your survey.