A team of researchers is writing a paper on a particular kind of program for older adults in the U.S. (because the work is incomplete, they prefer not to share too many details). The number of programs varies by state and the states in turn vary by the share of the older adult population (age 65 years and older). Their first visualization—the map shown here (using this data)—plots the quintiles of the number of adults per program.

The researchers are seeking help on three issues. First, should the visualization plot (a) the number of programs per 100,000 people or (b) the number of older adults per program? Second, if they create the map, what software program should they use (this map was created using this ‘Map Maker tool‘)? Third, what color scheme can they use that is consistent with black and white printing?

The research team sent in this updated map and wanted to thank everyone for their help.