The phrase <em>"from 1996 to 1997, the number of students in RSM doubled" </em>indicates that in 1997 there were twice as many students as there originally were in 1996. This means that if there were students in 1996, then another new students enrolled in RSM in 1997. Whatever the original number of students was, that same number was added to itself the following year. That is equivalent to saying that the number of students inncreased by 100% from 1996 to 1997.
