Spending on ambulatory care has increased recently, with more than half of it going to physician offices, according to Census Bureau data. Spending on ambulatory services rose 23.5% from 2007 to 2012. Physician offices earned about $405 billion from ambulatory care in 2012, up 20.6% from the approximately $336 billion earned in 2007. Not surprisingly, the ambulatory workforce also grew during the same period, from 5.7 million workers in 2007 to 6.6 million in 2012, a 15% increase.
Source: Census Bureau, November 2014