The following sources were cited in SAP Digital Futures Issue 13 Building Better Business Models.

Intangible assets make up 84% of the value of the S&P 500.
Kristi L. Stathis, “Ocean Tomo Release 2015 Annual Study of Intangible Asset Market Value,” Ocean Tomo Insights Blog, March 5, 2015, http://www.oceantomo.com/blog/2015/03-05-ocean-tomo-2015-intangible-asset-market-value/

A third of large companies’ revenue will be threatened by digital disruption by 2020.
Peter Weill and Stephanie L. Woerner, “Thriving in an Increasingly Digital Ecosystem,” MIT Sloan Management Review, June16, 2015, http://sloanreview.mit.edu/article/thriving-in-an-increasingly-digital-ecosystem/

The average life-span of a publicly traded company has dropped from 67 years in 1920 to 15 years today.
Bourree Lam, “Where Do Firms Go When They Die?” The Atlantic, April 12, 2015, http://www.theatlantic.com/business/archive/2015/04/where-do-firms-go-when-they-die/390249/

In 10 years, 40% of the current Fortune 500 may no longer exist.
Tech Trends 2014: Inspiring Disruption (Deloitte University Press, 2014), http://www2.deloitte.com/content/dam/Deloitte/us/Documents/consumer-business/us-cp-darwin-tech-trends-2014-social-activation.pdf

Three out of four current S&P 500 firms will be replaced by new ones by 2027.
Bourree Lam, “Where Do Firms Go When They Die?” The Atlantic, April 12, 2015, http://www.theatlantic.com/business/archive/2015/04/where-do-firms-go-when-they-die/390249/