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Using Icon Sets to Segregate Data
■ Four-icon sets—For the four-icon sets, there are two varieties of arrows: a black-to-
red circle set, a set of cell phone power bars, and a set of four traffic lights. In the traf-
fic light option, a black light indicates an option that is even worse than the red light.
The power bars icons seem to work well on both color displays and monochromatic
printouts.
■ Five-icon sets—For the five-icon sets, there are two varieties of arrows, a five-power
bar set, and an interesting set called “5 Quarters.” This last set is a monochromatic cir-
cle that is completely empty for the lowest values, 25% filled, 50% filled, ...