Point symbols represent discrete physical features (for example, triangulation points, address locations, fire hydrants, or street signs) or conceptual features (for example, cities by population, population by counties, birth rate, or unemployment rate by country, or disease outbreaks between 1990 and 2014 by region).
ArcMap offers four tools to represent quantitative data:
Graduated colors: This varies the hue (color) to symbolize the attribute values grouped into a given number of classes.
Graduated symbols: This varies the size and keeps the hue (color) constant to symbolize the attribute values grouped into a given number of classes.
Dot density: This keeps the size and hue (color) constant to symbolize the data that is not classified; the number of dots is tied to a certain attribute value.
Proportional symbols: This keeps the hue (color) and shape constant and varies the size that is tied to the highest and lowest attribute values and a given number of...