"Colorado has done excellent record keeping on the age of its enrollees. It might make a better bellwether for how things are going when it comes to reaching those under 35. What you see, in the graph below, is young-adult enrollment well below target levels -- but also increasing over time. During the first two months of open enrollment, 17 percent of those signing up for coverage were under 35. In early December, that rose to 20 percent and, for the last two weeks of that month, just about a quarter of those enrolling were in the much-coveted young adult demographic." Sarah Kliff in The Washington Post.