Clarification needed. The three classes given based on the language used (such as "Between 2% and 7%) are 0% <= x < 2% (low), 2% <= x < 7% (intermediate), and 8% < x <= 100%. This appears to leave out the entire range of 7% <= x <= 8%. What's that actual class ranges? If intermediate is actually 2% <= x < 8%, then it should probably be stated as something similar to, "Between 2% and 8%"