A16 has a thorough rundown of the economic structures of venture capital. This paragraph on the impact of VC on the US economy really stuck out to me.

Yet the entrepreneurial ecosystem that VCs have the privilege to help fund punches well above its weight in terms of impact on the U.S. economy: According to a study conducted at the Stanford Graduate School of Business, 43% of U.S. public companies founded since 1979 were funded by venture capital. These companies now comprise 38% of all employees, 57% of the total U.S. market capitalization, and account for 82% of all R&D spend – a proxy for further innovation growth – in the United States.