The 7 best universities in the US

There are many ways to calculate which school is best for you, but the ranking that attracts the most attention every year is U.S. News & World Report's annual Best Colleges Rankings — and this year is no different.

U.S. News & World Report assessed more than 1,800 U.S.-based colleges and universities to calculate the best in the U.S. The ranking considers student outcomes, faculty resources, financial resources, expert opinion, student excellence and alumni giving.

Read on to see the seven best universities in the country:

New York, New York

Total undergraduate enrollment: 6,113

Tuition and fees (2017-2018): $57,208

Average first-year student retention rate: 99 percent

Cambridge, Massachusetts

Total undergraduate enrollment: 4,524

Tuition and fees (2017-2018): $49,892

Average first-year student retention rate: 98 percent

Stanford, California

Total undergraduate enrollment: 7,034

Tuition and fees (2017-2018): $49,617

Average first-year student retention rate: 98 percent

Chicago, Illinois

Total undergraduate enrollment: 5,941

Tuition and fees (2017-2018): $54,825

Average first-year student retention rate: 99 percent

New Haven, Connecticut

Total undergraduate enrollment: 5,472

Tuition and fees (2017-2018): $51,400

Average first-year student retention rate: 99 percent

Cambridge, Massachusetts

Total undergraduate enrollment: 6,710

Tuition and fees (2017-2018): $48,949

Average first-year student retention rate: 97 percent

Princeton, New Jersey

Total undergraduate enrollment: 5,400

Tuition and fees (2017-2018): $47,140

Average first-year student retention rate: 98 percent

At the top of the list is Princeton University, which received a perfect 100 out of 100 score. One area that helped Princeton edge out competitors like Harvard was its sky-high student retention rate. Ninety-eight percent of first-year students at Princeton return for a second year.

Keeping students on track to graduate can be a difficult task especially at these particularly expensive and rigorous institutions. By providing significant academic and financial support, schools like the University of Chicago and Yale University maintain close to 100 percent first-year retention rates.

Brian Kelly, editor and chief content officer of U.S. News, says that retention is one of the most important factors to consider when choosing a college. "Before taking out student loans or writing a tuition check, families should research graduation and retention rates. These are important indicators of how well a school supports its students both academically and financially," he said in a statement.

"Colleges that saddle students with debt but do little to support them through graduation are contributing to a vicious cycle — without that valuable degree, students will have a difficult time landing well-paying jobs and repaying their loans, which puts them in a precarious financial situation early on in their careers."

All of the 10 highest-ranked schools have impressive graduation and retention rates. The average six-year graduation rate is 96 percent for the top-10 universities compared to just 71.7 percent across all American universities. The average freshman retention rate among the top universities is 98.3 percent, compared to 87.2 percent nationwide.

Of course, there are many other ways to rank universities. Stanford professor Raj Chetty and Harvard economist Nathaniel Hendren found that mid-tier public schools were actually the best at helping move students from the bottom fifth of income distribution to the top fifth, and The Princeton Review ranks schools based on how much or how little students study.

No matter how you choose to rank universities, the key is finding the school that is best for you.

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