
Maps usually gray out Greenland, and other places like North Korea and Antarctica, and the color key will put gray for ‘No Data’. North Korea and Antarctica make sense but I have no idea why Greenland is always labeled as ‘Na Data’. Once you notice it once, you’ll notice it on every color-coded map you ever see.
Greenland is labeled that way because it’s part of Denmark, and Denmark usually doesn’t report data specific to Greenland. But this isn’t common knowledge, and most people would get confused if they saw Denmark’s statistics associated with Greenland. Sometimes they’ll show no data for Western Sahara (if they show it at all) because it’s not recognized as independent (Morocco says it’s their territory)