It looks like the authors relied on several sources. They write: “To analyze how VC deal activity responded to the COVID-19 pandemic and attendant economic cr

It looks like the authors relied on several sources. They write: “To analyze how VC deal activity responded to the COVID-19 pandemic and attendant economic crisis, we use data from Pitchbook, CB Insights, and Capital IQ. We tabulate VC investment deals in U.S.-based startups by industry and sector using the Pitchbook and CB Insights data. Pitchbook has the advantage of broader coverage, while CB Insights has the advantage of detailed company descriptions, which enable us to assess changes in financing for particular types of businesses in sectors especially hard-hit by the crisis.”