The Trough of No Value

"The problem is that many kinds of objects go through a period in their potential lifespans when they don't "pencil out"—they're not worth keeping or preserving because they're not worth any money. Here's an approximate graph of the typical value of many types of objects. The x-axis is time and the y-axis is value; the horizontal line is $0."


http://theonlinephotographer.typepad.com/the_online_photographer/2009/02/the-trough-of-no-value.html