How to Interpret this Chart
Each EV spread used by this Pokemon was classified into various categories. A single EV spread can go into multple categories.
Example: A Zapdos running Calm:248/0/0/0/244/16 (a popular set in Monotype) would be classified as:
This chart tells you what percentage of sets run by this Pokemon meet this criteria. To view the individual sets that were classified this way, click on a spread classification. The percentage in the chart that appears corresponds to that set's contribution to a particular classification.
e.g. I know 82% of Skarmory run Max HP from this "Spread Classification" chart. Then, using the chart the pops up from clicking Max HP, I learn 30% of the Skarmory that run max HP run Impish:248/0/236/0/0/24