Most experts agree that experienced research and development professionals should have plenty of career opportunities with pharma/biotech companies in the coming years. More illnesses are being treated with drug therapy, particularly among elderly patients. As the average age of the population increases, pharmaceutical sales will increase, allowing companies to spend more on research and development. There are also record numbers of drugs being developed for mental health disabilities. Many drug companies will also be focusing on gene therapy, immunotherapy, and ethnobotany (the study of medicinal plants). According to the U.S. Department of Labor, employment of medical scientists is projected to grow 8 percent through 2024, about as fast as the average for all occupations. The DOL reports that "a larger and aging population, increased rates of several chronic conditions, and a growing reliance on pharmaceuticals are all factors that are expected to increase demand for medical scientists."