Online education enrollment has continued to grow according to the new report, Digital Learning Compass: Digital Education Enrollment Report 2017. The overall enrollment in higher education, however, has fallen in the past three years.

In 2015, nearly 30 percent of college students from more than six million took at least one online course. Nearly half took courses exclusively online. The report showed online enrollments at private, nonprofit institutions have grown at the fastest rate.

For-profit institutions have experienced a decline in enrollment. The nonprofit institutions now enroll more distance students and have seen growth in both undergraduate and graduate students.

The Chronicle of Higher Education reported that online enrollment still remains concentrated as 5 percent of institutions account for nearly half of all distance-education students. In 2015, 50 institutions with most online students enrolled more than 1.4 million students.

The report ranked the 50 colleges with the biggest enrollments in 2012 and the 50 biggest in 2015. The changes in the online-education landscape showed 46 out of 50 changed rankings over the three years.

Jeff Seaman, co-director of Babson Survey Research Group conducted the survey with the WICHE Cooperative for Educational Technologies and the ed-tech blog e-Literate. Seaman said the survey has not yet reached the steady state in terms of who the big players are.

The data showed that 17 colleges that had the largest enrollments in 2012 were replaced by faster-growing institutions in the 2015 list. Southern New Hampshire University was one of the the fastest growers, which grew by nearly 400 percent. Western Governors University, Brigham Young University-Idaho, the University of Central Florida, and Grand Canyon University had an increase of more than 10,000 students.

Click here to view to list of a table showing the change in online enrollments from 2012 to 2015 for the 50 institutions that had the most online enrollments in 2012.