Hello everyone, From the book Thank You for Being Late by Thomas Friedman. For all of the above reasons, 2007 was also “the beginning of the clean power revolution,” said Andy Karsner, the U.S. assistant secretary of energy for efficiency and renewable energy from 2006 to 2008. “If anyone in 2005 or 2006 told you their predictive models captured where clean tech and renewable energy went in 2007 they are lying. Because what happened in 2007 was the beginning of an exponential rise in solar energy, wind, biofuels, LED lighting, energy efficient buildings, and the electrification of vehicles. It was a hockey stick moment.” I can't figure out the meaning of "their predictive models captured where clean tech and renewable energy went in 2007." What's the general meaning of this phrase? Thank you.