Sustainability Indicator: 59% Payback

Today's sustainability indicator, 59 percent, is the proportion of corporate emissions-reductions efforts that pay for themselves in 3 years or less.

This month's indicators:

$10 billion: annual savings on U.S. electric bills from new lightbulb standards.
30: large power plants it takes to produce the 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.
13 million tons: CO2 emissions saved by Wal-Mart's recycling and waste-reductions last year.
2.3 million: cars needed to be taken off the road to reduce CO2 emissions by 13 million tons.
240 gigatons: mass lost from the Greenland ice sheet each year from 2002 to 2012.
0.7 millimeters: annual sea level from the melting Greenland ice sheet.
61 percent: amount of Spain's electricity demand that was met by wind power on April 16
396.53 parts per million: carbon dioxide in the atmosphere as of April 14.
350 parts per million: maximum CO2 before environmental damage from climate change.
130 billion pints: beer consumption expected in China in 2016.
29%: increase in China's 2016 beer consumption over 2011.
$1 trillion: worldwide investments in renewable energy through 2011.
82%: decline in solar panel prices since August 2009.
117,182: electric cars and hybrids vehicles sold globally last quarter.
49%: rise in electric and hybrid sales compared with the same quarter a year ago.

Visit www.bloomberg.com/sustainability for the latest from Bloomberg News about energy, natural resources and global business.