This project is based on "Google Analytics API" to read the raw data, and I use the "Landing Page" as X-axis, and visits as "Y-axis", the X-axis is the percentage of the rows of landing page, the Y-axis is the percent of accumulated visits percentage, so it start as (0,0) and reach the end (100,100).
I add the color and size of the line to show the difference, the latest line (latest month) is red line, the nearest line is darker, and the earliest one is lighter, so you can see the "involving" of these lines.
And I try to define a index called "Distribution Score", that is the area of line above, if the visits of every page are the same, it will be like a straight line (red line) following:
If your website are popular in few pages, it will show like this:
You can see the line will reach over nearly 80% visits at first 5% rows, this is far beyond 80/20 rules, that is the first 20% items, accumulation more than 80% amount.
By now, this will be a good way to evaluate the effort of SEO, because if we look through the "Landing Page Distribution Score" and "Keyword Distribution Score", the percent of reach from search engine will be higher. But we can talk about this next time, the following is gallery of these chart which have done.
By now, you can notice that the "distribution score" of some site is getting better, but some are getting worse, and other are keep status quo. Using these images, you can easily identify your work of SEO, if you want to try, you can login in http://seokpi.analysis.tw/ to check it out, both of your landing chart and keyword chart. Have Fun~~