Sam Gindin pointed me to a history of private sector union density—the percent of workers belonging to unions—going back to 1900. (They’re credit to Troy and Sheflin’ Union Sourcebook, a standard source.) No doubt these numbers are more approximate than recent ones, but here’s a striking fact: 2018’s level, 6.4%, is a hair below 1900’s level, 6.5%. For simplicity’s sake, let’s just say they’re the same. Here’s an update of yesterday’s graph. Back where the 20th century started. That’s 118 years of progress for you.