Piketty Saez Income Shares

Replicates the core empirical relationship from Piketty & Saez (2003 QJE, 2007 JEL): the U-shaped pattern in US top income shares over the 20th century tracks closely with changes in top marginal income tax rates. Uses World Inequality Database (wid.world) public data, which updates the series through 2022. Tests whether tax-income share correlation persists in the post-2000 era.