9-Did the education system contribute to the Great Divergence? Yes, in a big way.
In a modern economy, widely shared prosperity depends on rising education levels. Innovation typically creates a need for a workforce with higher skills. From World War II through the 1960s, the U.S. economy mostly boomed and incomes grew more equal; not coincidentally, the high-school graduation rate climbed from 51 percent to more than 70 percent. Starting in the 1970s, the high-school graduation rate declined and then leveled off at 70 percent. The economy boomed again in the late 1980s and late 1990s, and many prospered, but this time the prosperity wasn’t shared equally because the supply of high-school graduates didn’t rise with growing technology-driven demand. The flat line in this chart creates inequality.