Indicator of Tourism industry supportive institutions and policies  (WTTC, mean of the years 2017-19).

This indicator is based on primary data on average National Park (IUCN category II) fees for international visitors expressed in US dollars calculated at market exchange rates, collected at country level. Reference: Van Zyl et al. 2019 National park entrance fees: a global benchmarking focused on affordability PARKS VOL 25.1 MAY 2019. 10.2305

Nature-based tourism economy indicator

This indicator measures sensitivity to pandemic and economic crises affecting international travels and tourism. Nature-based tourism industry is of one of the most important revenue sources for protected areas. the indicator is derived from standardisatoin in a range 0-1 of the Leisure Tourism Spending share of the country GDP (World Tourism and Travel Council), weighted by country naturalness index (Global Competitveness index of the World Economic Forum).

Share of tourism revenue in protecd areas budget. Steven R, Castley JG, Buckley R (2013) Tourism Revenue as a Conservation Tool for Threatened Birds in Protected Areas. PLoS ONE 8(5): e62598. doi:10.1371/journal.pone.0062598​

Which protected areas are visited most frequently?

Average annual number of visitors to a protected area. Data are currently available for a limited set of sitesand from different sources, published in the study: Balmford A, Green JMH, Anderson M, Beresford J, Huang C, Naidoo R, et al. (2015) Walk on the Wild Side: Estimating the Global Magnitude of Visits to Protected Areas. PLoS Biol 13(2): e1002074. https://doi.org/10.1371/journal.pbio.1002074.