Stage 1. The subway line directions are expressed through the curves.

Stage 2. Complementary color is added to the outline of the subway route to reduce visual confusion.

Stage 3. The name of each subway line is displayed at transfer stations.

Stage 4. Regional traits are symbolized on the map.

Stage 5. The map resembles the geography of actual locations for intuitive use.

A person with color-blindness is able to find unfamiliar stations on the new map within 25 seconds, a task that took 53 seconds, or twice longer, with the previous map. An average person is able to conduct the same task at a rate that is 20% faster, 18 seconds compared to the 23 seconds with the previous map. Prioritizing the minority’s needs eventually influenced everyone. The map has been acclaimed through more than 40 different press releases, 400 blog postings, and thousands of SNS sharing since its official release. This social responsibility of the corporation has enhanced the brand image.