Roughly 3.6 million people have signed up for coverage through HealthCare.gov so far, putting enrollment on track to finish far short of last year's totals.

The numbers that matter: There’s just one week left in this year’s enrollment window. And though HealthCare.gov usually sees a surge of applications at the end of the sign-up window, enrollment would need to more than double, by Dec. 15, to match the 9 million people who signed up through the federal marketplace last year.