What's a PhD worth?

Here's another article in the nature that makes some good points about the worth of PhD.

"The number of science doctorates earned each year grew by nearly 40% between 1998 and 2008, to some 34,000, in countries that are members of the Organisation for Economic Co-operation and Development (OECD). The growth shows no sign of slowing: most countries are building up their higher-education systems because they see educated workers as a key to economic growth. But in much of the world, science PhD graduates may never get a chance to take full advantage of their qualifications"

PhD program use to be for science-loving driven people and the world want more innovation from academic science to solve the problems.