Quality of life is the egree of well-being felt by an individual or group of people. Unlike standard of living, quality of life is not a tangible concept, and therefore cannot be measured directly. Furthermore, quality of life consists of two components. The first is a physical aspect which includes such things as health, diet, as well as protection against pain and disease. The second component is psychological in nature. This aspect includes such things as stress, worry, pleasure and other positive or negative emotional states. It is virtually impossible to predict the quality of life of a specific individual, since the combination of attributes that leads one individual to be content is rarely the same for another individual. However, one can assume with some confidence the higher average level of diet, shelter, safety, as well as freedoms and rights a general population has, the better overall quality of life said population experiences. The Economist Intelligence Unit’s quality of life index is based on a unique methodology that links the results of subjective life-satisfaction surveys to the objective determinants of quality of life across countries.