Perhaps there is a better place to post this.  If so, my apologies.  I have just received the forums email invitation to participate in the 2011 Independant microstock Survey.  So I took a quick look at the 2010 survey portion that dealt with income vs portfolio size.  I will not fill out the survey form as I am somewhat concerned about the tabulation of at least this portion of the last (2010 survey).  My comments and concerns can be read at:
http://blog.microstockgroup.com/microstock-income-vs-portfolio-size/