Economic Policy Uncertainty Index for Poland: Data, Construction, and Validation
We construct a continuous monthly Economic Policy Uncertainty (EPU) index for Poland spanning January 2000 to June 2026, following the newspaper-based Baker-Bloom-Davis (BBD) methodology. The index uses six deep-history Polish newspapers (Rzeczpospolita, Parkiet, Gazeta Wyborcza, Dziennik Gazeta Prawna, Gazeta Polska Codziennie, and Puls Biznesu), scaled by article volume, standardized to unit standard deviation over a fixed 2000-2024 baseline (300 months), averaged across available papers each period, and normalized so the baseline mean equals 100. Because newspapers enter the panel at different dates, a naive expanding-panel average can jump at each entry point from a change in composition rather than real uncertainty. We correct for this using the BBD Appendix A splicing procedure: a backward chain-splice from the richest six-paper anchor panel that matches dispersion via a multiplicative scale factor and matches level via a multiplicative ratio over each overlap window, yielding an index that is level-continuous across all entry points. The index rises sharply during the COVID-19 lockdown, the 2022 energy crisis, and the 2023 change of government, with its largest reaction following the 2016 Brexit referendum -- an external event with major implications for Poland's economic-policy environment. In month-on-month changes, Poland's EPU is moderately correlated with the US (0.26) and global (0.25) EPU indices. Together with the event-based evidence, these modest correlations support our central finding: EPU Index PL captures economic policy uncertainty that is predominantly domestic, driven mainly by developments in Poland's own economic policy rather than merely international spillovers, though international shocks remain relevant insofar as they create uncertainty about Poland's own policy decisions.