A steady drop in average pay for college-educated workers from the 1970's to the mid-1990's is evidence of this.
Yet America is suffering from too many college-educated workers.
Today, the typical college-educated worker makes 73 percent more.
More than 15 years ago, college-educated workers earned about 40 percent more than high school graduates.
"If growth were coming from college-educated workers, we'd be exhausting the pool," he said.
In 1979, for example, the average college-educated worker earned 47 percent more than the average high school graduate.
What would be the effect of a massive increase in the supply of college-educated workers on their own wages?
Many of the middle-aged, college-educated workers have no doubts that there has been a structural change.
Top earners account for a larger percentage of total income, and college-educated workers command an increasingly large premium.
Journalism school graduates are the lowest-paid college-educated workers joining the labor force.