Japanese Prefectural Library Panel, 2001–2025

A verified 25-year panel of all 47 Japanese prefectural libraries, 2001–2025(1,175 observations, no missing years), together with the verification record,the quality flags and the analysis code. The source is the prefectural library statistics compiled annually by the JapanLibrary Association. Electronic files exist for the 2020–2025 survey waves; the2001–2019 waves existed only in print and were digitized for this study byoptical character recognition combined with manual reading. One hundredforty-seven columns, about 6,900 individual numbers, were verified against theprinted column totals, of which 138 reconcile exactly; 65 cells were corrected,each recorded with its evidence. The nine variables used in the analysis — population, loans, gate count,library budget, materials budget, full-time staff, certified librarians,holdings and acquisitions — contain no unverified years. Auxiliary variablesdo, and the released data flags them. Contents: the panel in long, wide and analysis-sample form; the cell-levelquality flags and correction log; the treatment and facility-renewal coding;the registry of all 22 tests; the analysis code; and Appendices A to C of theaccompanying article. Licence: CC BY 4.0. Please cite both this deposit and the original statisticspublished by the Japan Library Association.