This chart purports to show how facial hair styles in London changed from 1842 to 1972. You could call it "the Rise of the Razor."

The data comes from a study that sociologist Dwight Robinson did back in 1976, looking at facial hair trends from 1842 to 1972. His methodology was somewhat unusual — he paged through 130 years of the Illustrated London News and counted all the beards, sideburns, and mustaches he saw. More recently, a Reddit user made the chart of Robinson's findings.

Back in the 1880s, it seems like almost everybody in London had some type of facial hair — and beards were the most common. Sideburns dwindled in the 19th century, and mustaches came in vogue around the 1870s. But by the 1970s, when Robinson's study ended, facial hair was going out of style.

There are some obvious limitations to the study — the chart only represents trends for the type of elite men who would have appeared in the Illustrated London News. So it's an older, English set being tallied — there aren't any beatniks or hippies shown in the data. The study also leaves out men in uniform and, of course, people who weren't in London.

Why did all the beards, sideburns, and mustaches go away?

There are a couple of theories about why beards went out of style, and the most compelling might be the decades-long rise of the safety razor. Gillette sales went from nothing to global phenomenon extremely quickly.

Though the beardless trend began before the safety razor became ubiquitous, Gillette and other razor manufacturers either helped push shaving into the mainstream or, at the very least, made it cheaper and easier to jump on the clean-shaven wagon.

But there's another theory too — the ups and downs of beards, sideburns, and mustaches are just a product of fickle fashion. Robinson also made a chart building off another researcher's findings about skirt widths over time. Those rose and fell just like beards, so it might be the randomness of style that's to blame for both:

And what's happened since 1972? More recent data might show an uptick in beards and mustaches, but there hasn't been a formal tally done yet. All we can hope is that the world will put down their razors and be inspired to let their beards grow again — for sociology's sake.

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