Today's sustainability indicator, 81 percent, is the proportion of U.S. energy demand met from domestic sources last year, making it the most self-sufficient the county has been for almost 2 decades. Oil accounts for almost all imported U.S. energy.
This month's indicators:
59 percent: proportion of emissions-reductions efforts that pay for themselves in 3 years.
$10 billion: annual savings on U.S. electric bills from new lightbulb standards.
30: large power plants it takes to produce electricity equivalent to the lightbulb savings.
63 percent: surge in new solar capacity added in Europe last year.
57 percent: potential decline in new solar capacity in 2012 amid economic uncertainty.
$71 billion: investment by oil industry to develop low-emission biofuels in the last decade.
$43 billion: investment by U.S. government over the same duration.
170 degrees Fahrenheit: reading on traditional black rooftops on NYC's hottest day last year.
42 degrees: temperature reduction reached by energy-efficient white roofs.
2 million: premature deaths each year from cooking with primitive stoves or open fires
#2: rank of indoor pollution from stoves among environment health risks, after unsafe water.
$1.4 trillion: spending by people over age 60 in Japan last year as the population ages.
23.3%: record proportion of Japanese population over age 65.
1.7 billion metric tons: CO2 pollution saved by the 20-year-old Energy Star program.
2 years: time it takes to generate that much pollution from electricity to all U.S. homes.
1/3: proportion of world's antibiotics consumed in India, where new superbugs were found.
35.3 gigawatts: North Sea offshore wind capacity projected by 2020.
3.2%: EU electricity demand supplied by 35.3 gigawatts.
2.5 billion: people worldwide who don't have bank accounts, which can reduce poverty
16%: banking done by mobile phones in Sub-Sahara Africa, where bank access is limited.
77 cents: income women in the U.S. receive for every $1 paid men get doing the same work.
1: the number of occupations, out of 265, where women get paid more than men.
70%: proportion of world's population that will be living in urban areas by 2050.
50%: world's population currently living in rural areas.
$5 trillion: global investment in clean energy by 2020 to contain climate change.
$409 billion: worldwide government subsidies given to the fossil-fuel industry in 2010.
$66 billion: global subsidies for renewable energy in 2010.
$90 billion: wealth of the richest 70 members of China's National People's Congress.
$7.5 billion: wealth of all 660 top officials in the three branches of U.S. government.
134: earthquakes last year in central U.S., where seismic activity is linked to fracking.
21: average annual earthquakes in central U.S. in the three decades prior to 2000.
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