The new release of the political constraint dataset expands the scope of coverage to 234 countries from 1800 to the present day. The new database also includes country codes from the cross-national time series data archive, Polity and the World Bank to facilitate matching this dataset to other international datasets.
Further information about POLYCON can be obtained from Norwegian Social Science Data Services
The Winzipped dataset (MS-Access format) and the codebook and non-technical notes (MS-Word format) are downloadable upon provision of contact details.
Freely available data on internet. Registration is required.