Home Power Magazine, Mar./Apr. 2014, by Vaughan Woodruff.
http://www.homepower.com/articles/solar-electricity/design-installation/become-solar-professional

"In 2012, the solar industry saw a 13.2% increase in employment in the United States—nearly six times higher job growth than in the rest of the U.S. economy. And in 2013, the industry experienced a 20% growth in solar jobs—10 times higher than the national employment rate. This trend is expected to continue as increasing demand for solar will require new professionals involved in the installation, design, sales, and manufacturing of solar heating and photovoltaic (PV) systems."