A new Data Brief from the Centers for Disease Control and Prevention (CDC) that is derived from the 2014 National Health Interview Survey indicated that about 17% of working-age adults lacked a usual place for medical care, ranging from 3% in Vermont to 27% in Nevada. The share of adults who did not have a general doctor visit in the past 12 months ranged from 16% in Vermont to 48% in Montana.
The Data Brief can be accessed at http://www.cdc.gov/nchs/data/databriefs/db245.pdf.