Incandescent Bulb Lifetime

Two 40 W incandescent bulbs in the front bathroom burned out within a few days of each other. Being that type of guy, I know that I installed this bulb nine years ago:

Bulb base - install date
Bulb base – install date

The date is easier to read with the bulb in hand: 13 Feb 05. The (5 yrs) indicates the previous bulb in that socket lasted five years.

The other bulb date went in during March 09, so it survived only five years; the previous bulb lasted 6 years.

Even though 40 W incandescent bulbs are history, maybe I have enough spares on the shelf that the next owner can replace ’em with cheap LEDs.

This may not be science, but it does have numbers…