- ^ "Data Sources". Global Footprint Network. 2010-02-05. Retrieved 2010-02-05.
| ... that in 2006, the United Nations estimated humanity's total ecological footprint to be 1.4 planet Earths? In other words, humanity uses ecological services 1.4 times as fast as Earth can renew them?[1] |
| Other "Did you know" facts... | Read more... |