Source: Sood, Shih, Van Nuys, and Goldman, “The Flow of Money Through the Pharmaceutical System,” USC Schaeffer Center for Health Policy & Economics, June 2017, https://healthpolicy.usc.edu/wp-content/uploads/2017/06/usc_flow-of-moneywhitepaper_final_spreads.pdf (accessed September 1, 2021), p. 2.