Data have become a key input into the production of many goods and services. But just how important? What is the value of data – their contribution to economic growth and well-being? This report discusses different approaches to data valuation, their advantages and shortcomings and their applicability in different contexts. It argues that the value of data depends to a large extent on the data governance framework determining how they can be created, shared and used. In addition, the report provides estimates of the value of data and data flows. Its focus is on the monetary valuation of data produced by private economic actors and their recording in economic statistics. Finally, the report puts forward a draft measurement agenda for the future.