As they say:
The Earth's biologically productive area is approximately 11.2 billion hectares, or 1.8 global hectares per person in 2002 (assuming that no capacity is set aside for wild species). Global hectares are hectares of biologically productive area with world-average productivity. This standardised measurement unit, or 'ecological currency,' makes comparisons of demand and supply possible across the world.
In 2002, humanity's demand on the biosphere, its global Ecological Footprint, was 13.7 billion global hectares, or 2.2 global hectares per person. Thus in 2002, humanity's Ecological Footprint exceeded global biocapacity by 0.4 global hectares per person, or 23 percent. This finding indicates that the human economy is in ecological overshoot: the planet's ecological stocks are being depleted faster than nature can regenerate them. This means that we are eroding the future supply of ecological resources and operating at the risk of environmental collapse.
It's not happy news, but tools like ecological footprinting are giving us understanding of the basic funamentals of our planetary situation, and insight into the big picture is, itself, a tool.
But from that graph it looks as if our footprint is actually leveling off. That could be viewed as good news considering that within the same period:
1) Our global population has nearly doubled
2) Industrialized society has spread to many parts of the developing world
3) That slightly more than half of the world's population has migrated to cities.
I view this graph as a challenge. Can we continue to reduce planetary footprint while at the same time allowing standards of living to rise in the developing world?
I think the doubling of the population is reflected by the biocapacity trend falling from 3.5 to 1.7 hectares/person in the same period
In response to the comment above, I think that developing countries (where speed is of the essence), it's nearly impossible. I wrote about a graph I saw on developing vs. industrialized countries and their respective footprints, and found: that every single country's ecological footprint invariably rises as the standards of living do.
I think it's people's quest for more stuff. For a group of people to live sustainably will not offset enough resources that people consume. Education doesn't seem to be the answer, so I'm actually leaning towards making people's choices for them - government regulation for power sources, city regulation with really small garbage cans, etc. It's unfortunate, but I think it needs to happen.