Education in New York City is provided by a vast number of public and private institutions. New York City is home to some of the most important libraries, universities, and research centers in the world. In 2006, New York had the most post-graduate life sciences degrees awarded annually in the United States, 40,000 licensed physicians, and 127 Nobel laureates with roots in local institutions. The city receives the second-highest amount of annual funding from the National Institutes of Health among all U.S. cities. It also struggles with disparity in its public school system, with some of the best-performing public schools in the United States as well as some of the worst-performing. Under Mayor Michael Bloomberg, the city embarked on a major school reform effort.