Education is the foundation for future generations of Californians' success and is routinely cited as one of the major drivers of economic growth. The CSU is by far the state's primary source of teachers: More than half of California's teachers are graduates of its campuses. In addition, education is growing as a field of study at the CSU. In 2007-08, nearly 13,000 CSU alumni received California teaching credentials. ​Mathematics and science teachers are especially important in preparing the workforce for the state's high-growth sectors. The CSU has increased its preparation of teachers in these fields by more than 85 percent in the past five years. Furthermore, 11 CSU campuses offer a three-year Ed.D. program designed to equip leaders with the necessary knowledge and skills to develop reforms to improve student achievement.​