How the figures are computed
The regional registers are read in full at each (monthly) update and counted municipality by municipality: only these counts are kept, never an individual record.
“Tourist dwelling” = habitatge d’ús turístic (Catalonia), vivienda de uso turístico (Andalusia), vivienda turística (Valencian Community), plus rooms in the host’s home in Catalonia; in Lombardy: holiday homes and apartments, tourist rentals, B&Bs.
Density = tourist dwellings / population × 1,000 (INE, Padrón municipal; ISTAT for Italy). Eurostat nights cover all accommodation sold via platforms, hotels included.
A municipality page is published from 5 registered establishments; it is offered to search engines only with at least 20 tourist dwellings and a second municipality-level indicator (bed places, company share, registration years or at least 30 Inside Airbnb listings).