Also: The case against arming teachers, and the unhelpful ways cities talk about bike helmets.
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What We’re Following
Mapping the housing crisis: Affordable housing is still scarce for America’s extremely low-income renters, with only 35 affordable rental homes for every 100 households in need, according to an annual study from The National Low Income Housing Coalition. That leaves a shortage of 7 million homes overall, and not one state or metro area has enough supply to close the gap. CityLab’s Sarah Holder explains the latest maps of America’s dire need for affordable housing.
Permanent record: A month after the Parkland shooting, thousands of students are staging a walkout today to protest gun violence—and a new study of law enforcement officers’ track record with armed assailants demonstrates why arming teachers is an incredibly bad idea.
More on CityLab
Map of the Day
Benjamin Schmidt, a history professor at Northeastern University, mapped historical census data to visualize when cities grew in the United States. You’ll likely recognize his data source—those tables on the side of nearly any town’s Wikipedia page—but you probably didn’t know that Wikipedia editor Jacob Alperin-Sheriff almost single-handedly entered the populations of 25,000 different cities and small towns reaching as far back as 1800.
The result is a scroll-worthy narrative map about urban/rural change in America. It’s not exactly mobile-friendly, so click away at your desk and your boss will think you’re working on something as important as the next transcontinental railroad.
What We’re Reading
New York City’s eye-catching export: luxury apartment towers (Quartz)
Don’t doubt Chicago neighborhoods’ commercial potential, receipts show (Next City)
Architect Richard Meier takes a leave of absence amid sexual harassment claims (New York Times)
Route 66 may be iconic, but the story of American Indians has been lost along the way (Mic)