Only about half of doctors in America identify themselves as “millionaires.” Like the rest of us, many physicians need to invest their money to grow it and build a retirement fund. And, increasingly, doctors are following the lead of the super-rich and investing in art. One-percenters are increasingly putting their money into art, which offers superior returns to the stock market averages with less risk and stress. Over time, the price of art tends to move in one direction — upwards — whereas stock prices can gyrate wildly and are prone to extreme volatility.