How important is it to graduate from college with a bachelor's degree in four years' time? For students piling on loan debt in order to finish their studies, I believe it would be crucial. Yet many students take five, six, or more years to complete a four-year degree program -- and a growing number of educational institutions are treating this as the new normal.

There are many factors to consider when choosing a college or university, and on-time graduation rates should certainly be among them. Here are four colleges that surpass their peers at launching students in a timely fashion, and -- not surprisingly -- excel in several other areas, as well.

Dartmouth College, Hanover, New Hampshire
A member of the Ivy League, Dartmouth is a superior educational value. The college has a four-year graduation rate of 88%, and also gets high marks for return on investment from PayScale -- ranking at No. 19 out of 1486 colleges, and No. 12 out of a total of 599 private, not-for-profit schools. Salaries are nothing to sneeze at, either: beginning salaries for graduates are in the $55,000 per year range, and Dartmouth is No. 38 out of 583 private schools for healthy mid-career pay levels.

Lafayette College, Easton, Pennsylvania
Lafayette graduates 89% of its more recent bachelor program students in four years, and sports an overall ROI of 44, and a rank of 28 when stacked up against its private-school peers. Typical yearly starting pay for graduates is a robust $57,600, and Lafayette claims a 95% employment rate for its recent graduates -- although graduate school enrollment and internships are included in that percentage, as well. The school comes in at No. 36 for mid-career salaries.

University of Notre Dame, Notre Dame, Indiana
This Roman Catholic University also sends 89% of its four-year degree program participants out into the world in the prescribed timespan, and has been awarded a stellar return on investment rating of 23 out of all colleges, and 15 for private schools. New University of Notre Dame graduates can expect to earn in the neighborhood of $54,000 per year, and the school ranks at No. 20 out of 583 for mid-career salary levels.

Williams College, Williamstown, Massachusetts
Williams College is a small liberal arts college that graduates a walloping 91% of its bachelor's degree students in four years' time. In addition, Williams College ranks 21 for ROI out of all colleges and comes in at No. 14 among its private-school competitors. Recent graduates earn a very respectable $50,400 upon graduation, and work their way up to an enviable salary level by mid-career, where the college ranks No. 17 among its peers.

Other things to consider
The U.S. government's College Scorecard site provides some additional tidbits of salient information. For instance, though Notre Dame and Lafayette are considered high cost, Dartmouth and Williams are more moderately priced. Another plus is the fact that median borrowing is low at the latter two colleges, at between $12,000 and $14,000 for an undergraduate degree -- whereas families typically borrow approximately $21,000 to pay for a course of study at Lafayette or Notre Dame.

Significantly, loan default rates at all four of these schools are very low -- between 1% and 1.3% -- compared with the national rate of 13.4%. Apparently, those high salaries help ameliorate the cost of student loan payments for graduates of these fine schools, a fact that should put these colleges at the top of most college shopping lists.