#overshootday.org

- The Ecological Footprint for Switzerland is 4.47 gha per person (in 2017)

- Global biocapacity is 1.6 gha per person (in 2017)

- Therefore, it would take (4.47/ 1.6) = 2.79 Earths if everyone lived like the Swiss

- We can determine Switzerland's overshoot day as 365 * (1.6/4.47) = 131th day in the year. The 131th day of 2021 is the 11th of May, Switzerland's Overshoot Day