Actually, this factsheet is propaganda disguised as a factsheet and even fails to provide the most basic understanding of what a "dropout" is, and the accuracy of this 71% graduation thing is called into question.
Use this article as reference instead
(actual dropout rates seem to be 15-20% for whites and 35% for minorities)
Also of interest, back when I was 18 and had to choose what kind of career I wanted to pursue/degree I wanted to get I really didn't know what I wanted to do and most people my age have the same problem. I only really knew what I wanted to do by the time I was 20 and many people I know still don't know what they want. Choosing early or earlier isn't a smart thing to do, either.