Innovation, fetishized by Silicon Valley companies and celebrated by business boosters, no longer provides the economic jolt it once did. From a report: In order to maintain Moore's Law -- by which transistor density doubles every two years or so -- it now takes 18 times as many scientists as it did in the 1970s. That means each researcher's output today is 18 times less effective in terms of generating economic value than it was several decades ago. On an annual basis, research productivity is declining at a rate of about 6.8 percent per year in the semiconductor industry. In other words, we're running out of ideas. That's the conclusion of economic researchers from Stanford University and the Massachusetts Institute of Technology. In a paper published this week through the National Bureau of Economic Research, "Are Ideas Getting Harder to Find?", economics professors Nicholas Bloom, Charles Jones, and John Van Reenen, and PhD candidate Michael Webb, defy Betteridge's Law of Headlines by concluding that an idea drought has indeed taken hold. "Across a broad range of case studies ... we find that ideas -- and in particular the exponential growth they imply -- are getting harder and harder to find," the authors declare in their paper.