In contrast to the continuously variable proportional circle maps, range-graded proportional circle maps have a set list of ranges that all data values fall into and limit the data to that number of circle sizes. The above map shows motor vehicle deaths in the state of California by dividing all of the data values into 5 ranges. With the data shown this way, a county that reported only 7 deaths by motor vehicle may come off looking like there were up to 907 deaths by motor vehicle. Therefore the data representation here can be misleading. However, this method is useful for recognizing general trends or patterns in phenomena. For example, there are much more deaths in the Los Angeles and San Francisco Bay areas, which could be correlated to higher populations and denser traffic congestion.
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