The physician shortage could reach 86,000 doctors by 2036, of which nearly half of the missing doctors could reflect shortages in primary care. One reason is demographics. The average age of physicians is 47 for women and 55 for men. Many of the older practicing physicians are among the Baby Boomer generation, who will be retiring soon and need care for themselves as they grow old. Another reason for the shortage is a 1996 federal law capping the number of graduate medical education training slots that Medicare will fund.