Polity II: Political Structures and Regime Change, 1800-1986

Carried out under the auspices of the Data Development for International Research (DDIR) project, POLITY II was designed to develop longitudinal indicators of political structures and regime change. This file encompasses most member states of the international system from 1800 to 1986, and consists of annual codings of regimes' structural characteristics, institutional changes, and the directionality of changes on underlying dimensions of democracy, autocracy, and power concentration.