Domestic Violence: over the 1993 to 2012 period, the number of Americans assaulted by an "intimate partner" fell by more than half, from 13.5 per thousand to 5.0.
Sexual Abuse of Children: Down 60 percent from 1990 to 2010. (Obviously this is really hard to measure, but if anything our data ought to be getting more complete, not less so.)
Drunk Driving. Fatalities caused by drunk drivers down 51% from 1982 to 2009.
Teen Pregnancy. Down 51% from 1990 to 2010.
Violent Crime. Down 49% from 1991 to 2014. (Murder bumped back up a little last year but other violent crimes continued to fall.)