Obviously technology creates more jobs than it destroys over time, because the nations who have developed the most technologies tend to have the lowest unemployment rates.
"By 2011, a significant gap appears between the two lines, showing economic growth with no parallel increase in job creation"
It seems the data set is US jobs only. In our new flat world, how many jobs did US-based companies create in other countries that previously were created in the US?
Not sure the US middle class has been destroyed, more that it has moved to other countries.