[xcyu]

The presentation from a16z comes to mind which had much more specific numbers comparing previous tech bubble to the current one. For example, the U.S. total funding in tech as % of GDP was 10.8% in 1999 vs. 2.6% in 2014 (slide 14). http://a16z.com/2015/06/15/u-s-tech-funding-whats-going-on/