In honor of Earth Day, the U.S. Department of Commerce’s Census Bureau has pulled together a sampling of green data  on green initiatives being taken to protect the environment.
According to the American Community Survey  (5-year estimates):
- 0.5% of Americans bike to and from work. More men bike to work than women (0.7% vs. 0.3%).
- 10.5% of U.S. residents carpool to work. Men are more likely to carpool than women (11% vs. 10%).
- 5% of U.S. residents take public transportation to work. Women are more likely to take public transportation (5.4% vs. 4.6%).
- About 36,000 households in the United States  rely on solar energy to heat their homes.
In 2009, according to data from the American Community Survey , the New York-Northern New Jersey-Long Island metropolitan area led in the nation in the percentage of workers who used public transportation at 30.5%, followed by the San Francisco-Oakland-Fremont metro area, at 14.6%.
The Census Bureau’s 2011 Statistical Abstract is an excellent source for additional green stats, including on solar and renewable energy  (PDF), emissions from power generation , air quality , threatened and endangered wildlife and plant species , and emissions of greenhouse gases by type and source  (PDF).