Estimates vary considerably regarding how many college students transfer. Several reports suggested about a third of college-aged students had transferred at least once during their college careers, which includes transfers from community or two-year colleges to four-year colleges, as well as transfers between four-year colleges or universities. A high estimate was that 60% of students attended more than one collegiate institution between the ages of 18 and 24, and this estimate includes 20% who transferred from one four-year institution to another one. A third estimate was that only 20% of students in four-year colleges were transfer students. A fourth estimate, from the National Center of Education Statistics, was that 2.5 million college students transferred each year. In 2009, one report was that 566,400 students at schools surveyed by US News, transferred from one institution to another in that year. A report in 1999-2000 suggested that a fifth of community college students intended to transfer to four-year colleges, and an additional 24% were taking courses for personal enrichment or for transfer purposes. Another report suggested that only about a quarter of community college students followed through on their plan to transfer to a four-year college or university.
Transfer students tend to be disproportionately from poorer families, according to one report. A report suggests that many transfer students have "far more experience in the ups and downs of the working world" and tend to bring more diversity to a college campus. A second report confirms that "transfers graduate at a higher rate than students who just finished 12th grade", and have "adjusted to a more independent lifestyle." Demographic analysis suggests that a slight decline in high school graduates is underway since about 2009, prompting many four-year colleges to make up for the shortfall by bringing in more transfer students.