One should note that the top 10 are relatively homogeneous societies with smaller populations. Note how the score goes down in proportion to the diversity in the population. Just how many minorities are living in Denmark? I am, however, surprised that Japan would be so low.
I would also like to see how far the lowest wages in their businesses compare with pay of CEOs in large businesses. For example, do they have a situation where the CEO of Walmart makes $21,000,000 while the lowest employees are paid $9 an hour. A society’s sense of fairness affects the unrest level.