April 22 marks the 42nd anniversary of Earth Day ― a day intended to inspire awareness and appreciation for the Earth’s natural environment. The day came from reaction to a massive oil spill in waters near Santa Barbara in 1969.

According the U.S. Census Bureau, the estimated revenue for residential nonhazardous recyclable collection services in 2010 for U.S. firms was up 26.5 percent from 2009 to $715 million.

Less than 2 percent, or 2.2 million, houses in the U.S. are heated by wood. Solar heating is event less common, with 38,100 households in 2010 using the sun. This compares to the 57 million housing units that use gas for heat.

Of the new single-family homes built in 2010, 88 percent included air conditioning. In 1974, it was 48 percent.

The average commute time for workers 16 years and older across the country in 2010 was 25.3 minutes, up from 25.1 minutes in 2009.

The average size of a single-family house built in 2010 was 2,392 square feet, down from 2,438 square feet in 2009.