Understanding proportional symbols
Features, layers and visual encoding
A graduated symbol map scales point symbols using a numeric property such as sales, visits or market score. Larger symbols represent larger values within the supplied data.
The visual range is relative to the minimum and maximum values. A single extreme value can make most other symbols appear similar.
How to read the map
Confirm the property is numeric and investigate missing or extreme values. Symbol area can look more dramatic than the underlying numeric difference, so inspect exact values when precision matters.
Use a categorical map when the property represents names or classes rather than magnitude.