Shade countries on a world map

see this spreadsheet: [login to view URL] There is 23 companies I need a map of the world what highlights all of the countries listed here. If the same country is listed more than one time, make shading darker. e.g. listed once: make it light grey, listed twice: make it grey , listed three times: make it dark grey. You world map should look very simple, so when I present it on a presentation it looks really sharp. Include some relevant sample in your bid. (please no spam bidders)