Why is Arizona State so large, and why does it keep growing?

Arizona State University reached a new milestone in the 2017-18 school year, enrolling more than 100,000 students for the first time.

Enrollment figures show ASU has 103,567 students, a 5-percent increase over last school year and 40 percent more than five years ago.

Tempe remains the largest ASU campus with an enrollment of about 51,000. With ASU's student body growing by leaps and bounds, here are answers to some common questions about enrollment at Arizona's largest public university.

Where are all the other ASU students?

About 30,000 ASU students are enrolled in online-only classes and don't set foot on campus.

The remaining ASU students are mainly spread over the downtown Phoenix, Polytechnic and West campuses. Outside the Valley, the smaller ASU Colleges at Lake Havasu City has operated since 2012.

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How did ASU get so big?

ASU's large size is not by chance.

The Arizona Board of Regents, who oversee the state universities, decided years ago to stick with three schools rather than starting new universities. The regents positioned ASU to take on the most of the growth.

The decision to have only three universities has sometimes been criticized by legislators and parents, who have questioned why there isn't a system of lower-priced, four-year state colleges.

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The idea has never gathered much traction, however, largely because it would require significant funding to get started.

How large could ASU grow?

The 2017-2018 enrollment increase puts ASU on track to have 125,000 students by 2025, a goal set by the Arizona Board of Regents as part of a strategic plan to increase the numbers of adults with college degrees.

How do NAU, UA compare?

Besides ASU, there is the University of Arizona with 44,831 students and Northern Arizona University with 30,704 students. Both of those schools saw enrollment increases over the last school year, but not to the same degree as ASU.

What are ASU's most popular majors?

Here's a look at the most popular majors at ASU:

1. Business: 7,035.

2. Psychology: 4,235.

3. Biological sciences: 2,895.

4. Interdisciplinary studies: 2,590.

5. Criminology and criminal justice: 2,356.

6. Computer science: 2,180.

7. Electrical engineering: 2,162.

8. Communication: 2,026.

9. Nursing: 1,745.

10. Mechanical engineering: 1,657.

A student's major will dictate which campus he or she attends in many cases, unless they are enrolled in only online classes. Journalism and nursing students are on the downtown Phoenix campus, for example. Some majors are available on more than one campus.

To help students figure out which campus might be the best fit, ASU has an online quiz that takes prospective students through a series of questions.

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