The index was first developed by economist Arthur Okun in the 1970s, and it is calculated by adding the unemployment rate to the inflation rate. The higher the index, the greater the economic hardship faced by the country's citizens.

The Misery Index is often used as a measure of how well an economy is performing, with a high index indicating a poor performance and a low index indicating a good performance.

The idea behind the index is that high unemployment and high inflation are both factors that contribute to economic hardship, so by adding them together, you get an overall measure of how well the economy is doing.

It's worth noting that the Misery Index is a simple and broad indicator and it's doesn't take into account other factors that can affect the economic well-being of a country's citizens such as GDP, income inequality, access to healthcare, education and housing.