The paper reports that although venture capital averaged less than three percent of corporate R&D from 1983-1992, it was responsible for almost eight percent of US industrial innovations during the same time period. The findings are based on a study of the influence of venture capital on patent activity across 20 industries over three decades.
Link
http://www.rje.org/abstracts/abstracts/2000/Winter_2000._pp._Kortum.html