Gabriel Zucman is an assistant professor of economics at UC Berkeley who specializes in inequality, wealth and taxation. In his book, The Hidden Wealth of Nations, Zucman shows that about 8 percent of the world’s household financial wealth is held in offshore tax havens, mostly by very rich individuals. Since 2015, he has served as co-director of the World Wealth and Income Database, a database providing access to extensive data series on the world distribution of income and wealth.