As the US transitions from an industrial to postindustrial economy, there are fewer manufacturing jobs, and more jobs based around creating and processing information.
But the defining change is that postindustrial societies shift away from an economy based on raw materials and manufacturing, to an economy based based on information, services, and technology.
And all of this keeps going in Lenski’s scheme of things, with specialization and technological innovation continuing, until the development of the computer, a technology that gave rise to the postindustrial society.