The blue line at the top is the United States; the other lines represent other advanced OECD countries. Krugman is surprised by the turnaround:
I grew up in the America marked by that peak in violence — the America in which Times Square was a nest of drug addicts and porn shops, and people were afraid to take the subway. Now it’s another world. And that’s one reason I find all these laments about declining values among non-elite Americans hard to take seriously. If things like single parenthood were as bad as they say, how can social pathologies have declined so much?(Via Crooked Timber)