From the American Association of Colleges of Nursing:
According to the Bureau of Labor Statistics’ Employment Projections 2010-2020 released in February 2012, the Registered Nursing workforce is the top occupation in terms of job growth through 2020. It is expected that the number of employed nurses will grow from 2.74 million in 2010 to 3.45 million in 2020, an increase of 712,000 or 26%. The projections further explain the need for 495,500 replacements in the nursing workforce bringing the total number of job opening for nurses due to growth and replacements to 1.2 million by 2020.