What janitorial jobs reveal about rising inequality

"To Understand Rising Inequality, Consider the Janitors at Two Top Companies, Then and Now," by Upshot's Neil Irwin, on the N.Y. Times Business cover:

• Gail Evans, now a global chief information officer, was a janitor in Building 326 at Eastman Kodak's campus in Rochester in the early 1980s. Marta Ramos cleans at Apple's headquarters.
• "In the 35 years between their jobs as janitors, corporations across America have flocked to a new management theory: Focus on core competence and outsource the rest. The approach has made companies more nimble and more productive, and delivered huge profits for shareholders. It has also fueled inequality and helps explain why many working-class Americans are struggling even in an ostensibly healthy economy."
• "[I]n the 21st-century economy, many millions of workers find themselves excluded from [foosball tables and free sushi]. Rather than being treated as assets that companies seek to invest in, they have become costs to be minimized."
• Go deeper.