GAO Employee Misclassification Report [1]
"The number of independent contractors in the total employed workforce grew from 6.7 percent in 1995 to 7.4 percent in 2005. In 2005, there were 10.3 million independent contractors. Independent contractors, in 2005, had an average age of 46 years, were almost twice as likely to be male than female, and almost two-thirds had some college or higher education. Independent contractors were employed in a wide range of industries (such as professional services and construction) and occupations (including sales and management)."
That is the opening paragraph from the United States Government Accountability Office (GAO)’s study on independent contractor misclassification in the construction industry (GAO-07-859T) [11] released on May 8, 2010 in a hearing before the Ways and Means Committee of Congress.
Follow the above link to read the remainder of the testimony and findings.