All internet data accessed in October and November 2010, double-checked and verified in December 2010.

1. Niagara Falls flow rate sourced from Recommended daily water consumption sourced from the Mayo Clinic, available at Data estimates of people without access to safe drinking water sourced from the World Health Organization, available at

2. United States marriage data sourced from the US Center for Disease Control, available at

3. United States birth data sourced from the US Center for Disease Control, available at Birth data for India and China sourced from the US Central Intelligence Agency, available at

4. Plane passenger and flight data sourced from the US Bureau of Transportation Statistics, available at and, respectively.

5. Solar energy impact rate sourced from, available at

6. Text message statistics sourced from the CTIA, available at

7. Data based on the usage rate of a 100-watt incandescent lightbulb and the US Census Bureau estimate of the number of households, available at

8. New York City subway data sourced from

9. New bike sales data for 2009 sourced from the National Bicycle Dealers Association, available at 2006 and 2007 shoe sales data sourced from the American Apparel and Footwear Association, available at

10. Based on 2007 emissions data sourced from the UN Millenium Development Goals Indicators, available at 2007 population estimates for the United States sourced from the US Census Bureau, available at

11. Data extrapolated from sales milestones reached on 9/9/2009 and 2/24/2010, sourced from