40W and 60W incandescent bulbs will no longer be produced

“The new light bulbs use less power to give off the same amount of light. Therefore, consumers will no longer be buying bulbs simply based on their power, expressed in watts, and will shift toward buying  bulbs based on their light output, expressed in lumens. In the near term, manufacturers are including claims like “replaces 60W bulb” or “13 W = 60 W” for a 13-watt CFL that gives off as much light as the old 60-watt incandescent bulb. “– Horowitz