1. Index
This compares audience composition of the site to the entire Internet population. The higher the index number, the more concentrated a site is in a particular demographic.
As an example, if a site indexes 100 for age 18-24, that means a given visitor to it is as likely to be 18-24 as any internet user chosen at random. An index of 200 means the visitor is twice as likely to be 18-24, 50 means half as likely, and so on.
2. Segments are represented with icons. Segments include gender, age, household, income, education and household.
3. Very High Indexes (over 200) are denoted with a plus symbol.
4. Internet Average is represented by the dotted vertical line.