There is widespread alignment among politicians, many policy experts, and foundations that support higher education that the United States must drastically increase the proportion of Americans who enroll in and complete college -- now a centerpiece of the Obama administration's agenda.

Without significant intervention, a federal study released Tuesday suggests, that common goal will be way out of reach.

A National Center for Education Statistics report released Tuesday projects key education data out to 2018 and estimates that college enrollments will increase by 13 percent by 2018, to 20.6 million, and that the number of associate and bachelor's degrees awarded by American colleges would grow by 25 and 19 percent, respectively. That growth would actually represent a slowdown from the pace of expansion in both enrollments and degree production since 1993, the study finds. (And it is conceivable that the United States would actually lose ground on college enrollment under this scenario, as the 13 percent increase in enrollment would occur at a time when the U.S. population is increasing by 14 percent.)

The study, which includes higher and lower projections as well as the mid-range projections viewed as the likeliest outcome, is based mostly on demographics and and historic trends, with some economic factors mixed in, says William J. Hussar, a financial economist at the National Center for Education Statistics and the report's co-author. It does not in any way try to account, he said in an interview, for any changes in federal policies or in behavior that might flow from new policies. "It's basically a look at what happens if current conditions hold," he said.

Under those current conditions, the country is on track to fall short of President Obama's goal -- which resonates with initiatives sponsored by the Lumina Foundation for Education and the Bill and Melinda Gates Foundation -- of returning the United States to the top of the list of developed countries in the proportion of citizens with a postsecondary credential. (Lumina's "Big Goal," for instance, is to increase the percentage of Americans with high-quality two- or four-year college degrees and credentials from 39 percent to 60 percent by 2025, an increase of 23 million graduates above current rates; Obama's American Graduation Initiative, which is included in student aid legislation the House of Representatives is expected to begin voting on today, aims to boost the number of community college graduates by 5 million by 2020.)

The Education Department projections make clear just how difficult it will be to get there from here, unless monumental changes occur. The study projects that 12 percent more undergraduates will enroll in college through 2018, with slightly higher proportions for graduate students (18 percent). Those numbers will be dragged down because the rate of increase in the number of high school graduates is projected to slow in the next decade, leading to an increase of just 9 percent in the enrollment of 18- to 24-year-olds in college through 2018. The enrollment rates for those 35 and older will be higher (12 percent) and those for 25-34-year-olds higher still (25 percent), the department predicts.

Enrollments of women and members of minority groups are expected to grow disproportionately, with increases for female students outpacing men (16 to 9 percent) and with enrollments of Hispanic (38 percent increase), Asian/Pacific Islander (29 percent), black (26 percent) and American Indian/Native Alaskan (32 percent) growing at significant greater rates than that of white students (4 percent).

The study projects that enrollments at public and private institutions will grow by the same amount -- 13 percent -- between now and 2018, but with one big caveat: the "private category" includes both nonprofit and for-profit institutions, and the center for education statistics cannot break them down further at this point, Hussar said.

The department also projects increases in the rates at which students earn degrees that, while significant, would fall far short of what would be necessary to reach the goals set by Obama and others. In addition to a 25 percent increase in associate degrees and 19 percent in bachelor's degrees, the study projects 28 percent growth in master's degrees earned and a 49 percent spike in the number of Ph.D.'s granted.

Dewayne Matthews, vice president for policy and strategy at the Lumina Foundation, said the data show exactly why his organization and so many others are focused on bolstering college going and college completion. "This shows what happens if things stay the same," Matthews said. "We are basically saying we need to change the equation."