The package of the Great Value (Walmart) 23 Watt Soft White Compact Fluorescent Bulbs state that they have a bulb life of, and I quote, "10,000 hours", "up to 9 years!* dura hasta 9 anos!*".
So when I put one of said bulbs that the government is forcing us to buy in the kitchen I decided to write the date and time on the white base. These bulbs lose life when they are turned on and off and since the kitchen light is left on 24/7 (tinker with it on pain of death) I figured it would be a good way to see exactly how many hours one gets out of the bulb. Because if it doesn't last 10,000 hours then I'm not saving the advertised "$77 in energy costs per bulb** Ahorre $77 en costos de energia por foco**".
From the time I put the bulb it was switched off a few times, probably no more than twenty. Since I have no way of knowing which family member turned off the light I figured it was better to offer "pain of death" to none instead of to all.
Today when I got home from work, the bulb was dark. Today... September 26, 2011. The date on the bulb (carefully extracted so as not to break it and incur the wrath of some hazmat team) was October 12, 2010... 11 AM. That's 351 days at 24 hours a day = 8,424 hours. Not bad. I saved an estimated $64 on the $4 bulb. SCORE!