In a prospective study, you have determined that graduate students have an incidence rate of 25 per 100 of carpal tunnel syndrome compared to only 5 per 100 of people employed in professional white-collar occupations. This was a 2 year follow-up study that began when the cohort of interest received their undergraduate degrees and all subjects were free of carpal tunnel syndrome at the beginning of the follow-up.

What is the graduate student's relative risk of developing carpal tunnel syndrome?