Executive education (Exec. Ed) refers to academic programs at graduate-level business schools worldwide for executives, business leaders and functional managers. These programs are generally non-credit and non-degree-granting, but sometimes lead to certificates. Estimates by Business Week magazine suggest that executive education in the United States is approximately an $800 million annual business with approximately 80 percent provided by university-based business schools. Key players in university-based executive education span elite[clarification needed] universities, as well as many regional and mid-sized universities and business schools around the world.