Could someone help me understand this plot?

What i guessed: 1. Participants were asked how happy they are. 2. After that they were asked about what percentage of people from /their own country/ would answer happy or very happy. 3. Plot XY of the ratio of people who answered happy or very happy (x axis) vs their average of the percentage of how this happy people estimate how many people answered like them (y axis).

Did I got it right?