http://bls.gov/opub/mlr/2004/07/art2full.pdf http://bls.gov/opub/mlr/2004/07/art2full.pdf indicates self-employment has fallen a lot over the last few decades.

http://bls.gov/opub/mlr/2004/07/art2full.pdf http://bls.gov/opub/mlr/2004/07/art2full.pdf indicates self-employment has fallen a lot over the last few decades. It doesn't have any data after 2003, so maybe there was a massive spike in self-employment, caused by casualization (fake self-employment, to avoid giving benefits to workers) and retrenched workers setting out as "consultants".