Similarly, today's manufacturing firms produce about as large a share of the gross national product as they used to with a much smaller percentage of the labor force.
Moreover, there's evidence that recent growth in some of the professions -- the law, higher education -- has been a bubble, and is about to burst.
The bad news for the Millennial generation that is entering its work years is that the economy of the future won't look like the economy we've grown accustomed to. The "hope and change" that Barack Obama promised hasn't produced much more than college loans that will be hard to pay off and a health care law that lets them stay on Mommy and Daddy's health insurance till they're 26.
The good news is that information technology provides the iPod/Facebook generation with the means to find work and create careers that build on their own personal talents and interests.
As Walter Russell Mead writes in his brilliant the-american-interest.com blog, "The career paths that (young people) have been trained for are narrowing, and they are going to have to launch out in directions they and their teachers didn't expect. They were bred and groomed to live as house pets; they are going to have to learn to thrive in the wild."
But, as Mead continues, "The future is filled with enterprises not yet born, jobs that don't yet exist, wealth that hasn't been created, wonderful products and life-altering service not yet given form."
As Jim Manzi argues in his new book "Uncontrolled," we can't predict what this new work world will look like. It will be invented through trial and error.
What we can be sure of is that creating your own career will produce a stronger sense of satisfaction and fulfillment. Young people who do so won't hate their work the way those autoworkers hated those assembly line jobs.