Ed,
Be careful, you're dating yourself. 2sh1's methodology is certainly accessible to anyone with a modern high school education. Remember that they study nuclear physics, advanced math and finance, and much more in high school now. This sort of financial analysis is pretty simple stuff for any decent math student now. I don't want to date myself (and I'm pretty sure that I'm younger than the majority of members here) but we didn't even study calculus when I was in high school, and I was in all the honours math and science courses at the time. It's much different today. Start around page 100 of this report and see what I mean:
http://www.edu.gov.on.ca/eng/curriculum/secondary/math1112currb.pdf
You know what they say, "Today's kids, sheesh!"