There’s a line that’s repeated throughout the 1987 movie Hollywood Shuffle as a sort of inside joke for black viewers who are watching: “There’s always work at the post office!” It’s a wink at a commonly uttered phrase by black people in America. But it’s also a quip with a serious material basis for black workers who have found in the US Postal Service employment stability and upward mobility for generations.

Many prominent black Americans paid the bills by working the mail as they pursued their larger ambitions. Dick Gregory worked as a postal worker in Chicago during the daytime before refining his stand-up routine at night. In between gigs, the jazz great Charles Mingus put on a USPS uniform. As he was building his career as a writer in the late 1920s and early 1930s, Richard Wright worked in the post office, and he referenced this experience in early novels. Even the famous communist Harry Haywood worked for the postal service after fighting in World War I.

For the average black worker, the postal service represents a stable, decent-paying career that is hard to find elsewhere. Today the average salary of a USPS employee is $55,000, and 21 percent of USPS employees are black. The history of black postal workers demonstrates the critical importance of government employment and a robust public sector for the advancement of black people in this country.