Iowa continues to lead the nation in high school graduation rates, according to finalized data released by the U.S. Department of Education. Data shows that 90.5 percent of Iowa’s seniors graduated from high school in the 2013-14 school year, up from 89.7 percent the year before. That compares with an 82.3 percent national average for the 2013-14 school year. Data also shows that Iowa’s education system is making progress in graduation rates among traditionally underserved students, including low-income students, minority students, students with disabilities and English language learners.