The wedding of Danish Crown Princess Mary and Crown Prince Frederik. Getty/Ian Waldie Denmark, you've come a long way since Hamlet contemplated his existential despair with a skull.

According to the World Happiness Report by the United Nations, which released an update Wednesday, people living in the Scandinavian country are the happiest in the world.

Economics researchers from around the globe, including the famed Jeffrey Sachs, used indicators of what they call "life-satisfaction" to rank the happiness of 157 countries. (The US took 13th place.)

The authors are careful to note that happiness is highly subjective, but they used three different aspects to try to come to a general measure of the feeling: residents' evaluations of their situations, positive feelings about their lives (like joy and pride), and their negative ones (like anger and worry).

Such self-evaluations go far beyond simple economics, touching fulfillment in civic and family life.

So what makes Denmark so special?