On January 1, 2014, as part of a 2007 energy efficiency law, the U.S. stopped producing and importing standard 40- and 60- watt incandescent bulbs. The law signed by former President George W. Bush requires new light bulbs to meet tighter standards.

60 W
For those not ready for the switch, most stores will continue to sell the 40- and 60- watt bulbs until supplies run out. However, switching out those old incandescent bulbs will reduce the energy needed to light up your room. Ninety percent of the energy used by an incandescent bulb is given off as heat. According to the U.S. Department of Energy, upgrading 15 incandescent light bulbs to CFL or LED bulbs could save about $50 per year.

Sources:

Energy.Gov, “Lighting Choices to Save You Money”

CBS News, “The old-fashioned light bulb is disappearing”