October 21, 2021 – The following figures rely on data from the American Community Survey to track trends among physicians from 2003 to 2013. See the Technical notes for more details on the methodology.

Figure 1.

Figure 1 shows steady growth in the physician workforce between 2003 and 2013 – roughly 20% over the period, or 1.9% growth per year. Because the US population grew roughly 9% over the same period, the number of physicians per capita also grew between 2003 and 2013.

Figure 2.


The vast majority of physicians work in either hospitals or ambulatory and outpatient settings. However there has been a major shift in work settings away from ambulatory settings and toward hospitals since 2003, when 38% of physicians reported working in hospital settings and 54% reported working in ambulatory and outpatient settings. By 2013, roughly 45% of physicians reported working in each setting. Some, or indeed much of the shift could be due to consolidation activity in which hospitals purchased or relocated ambulatory practices and physicians reported their employment setting as ‘hospital’ as a result.1

Figure 3.


Note: earnings figures include only full time physicians over age 35

Median earnings among physicians have remained relatively stable, accounting for inflation, since 2003. While in the 2000s, median earnings among hospital-based physicians were slightly lower than those in ambulatory and outpatient settings, they were the same by 2013. This phenomenon may be related to consolidation and vertical integration which has sometimes led to hospitals bidding up physician salaries in seeking to purchase practices.1

Figure 4. 


Hours worked among physicians (excluding those under 35, many of whom are residents) have gradually fallen over the 2003-2013 period, from an average of 51.4 hours to 49.5 hours (a drop of 4%), continuing trends we reported in earlier work.2 The percentage of physicians working more than 50 hours per week dropped from 44% in 2003 to 36% in 2013. Similar drops were found among physicians over age 50 and those between the ages of 35 and 49.

Figure 5.

Figure 5 illustrates the gradual aging of the physician workforce. Medical school enrollment grew rapidly in the 1960s and 1970s and was then relatively stable throughout the 1980s and 1990s and even 2000s. That pattern is reflected in the growth in physicians over age 50, who now make up more than 40% of the physician workforce and surpassed the numbers of physicians between 35 and 49. Just in the last several years, the number of medical schools has increased a significantly, which is reflected in the uptick in the numbers of younger physicians in 2012 and 2013.

Figure 6.

Figure 6 shows the proportion of female physicians gradually increasing over the time period, from 29% in 2003 to 34% in 2013. Recent medical school graduates have reached relative parity (50% female) in recent years and thus the proportion of female physicians in the future workforce is expected to increase. The proportion of young physicians (under age 35) that are female has actually dropped slightly since 2003, but remains at 50%. Similarly, the percentage of physicians that is non-white grew among the overall workforce from 24% to 29%, and is higher among younger physicians, reaching 40% by 2013.

Figure 7. 

It is well known that a large portion of physicians, particularly primary care physicians, come to the US to complete graduate medical education and to practice as a physician. According to the ACS data, 69% of physicians in 2013 were US-born. Among the 31% who are not, most came to the US more than 20 years ago, while 18% (and 6% of physicians overall) came to the US within the past 10 years.


Technical Appendix

In this brief, physicians are identified via selection of the “physicians and surgeons” occupational category in the American Community Survey by household respondents. All figures use survey weights provided by the Census and are further weighted by FTEs (an MD working part-time is only counted as ½). The total number of FTE physicians in 2013 (873,600) in Figure 1 is similar to the estimate of active physicians from the American Association of Medical Colleges from that year (830,000)3 and from a private database cited by the Kaiser Family Foundation for 2015 (904,000 professionally active physicians)4.

To protect individuals in the survey from possible identification, the survey administrator’s ‘topcode’ the earnings values for the highest 1 percent of earners in each state – that is, the survey reports not the individuals’ actual earnings, but an average of all individuals in that top 1% earnings group. Because a large number of physicians are in that group, and because averages are sensitive to large values, we report median earnings instead.

Authors: David Auerbach, Peter Buerhaus, and Douglas Staiger.


  • Baker LC, Bundorf MK, Kessler DP. Vertical integration: hospital ownership of physician practices is associated with higher prices and spending. Health Affairs 2014; 33:756-763
  • Staiger DO, Auerbach DI, Buerhaus PI. Trends in the work hours of physicians in the United States. JAMA 2010; 303:747-753
  • Center for Workforce Studies, American Association of Medical Colleges. Physician Specialty Data Book. November, 2014
  • Foundation KF. Professionally Active Physicians. 2015;