happy life expectancy happy life expectancy happy life expectancy (hle) is calculated by multiplying life expectancy by a happiness index. the first uses life expectancy at birth. the happiness index is the average appreciation of life (with a value from 0 to 1) from the world databases of happiness. quality of life indexes arguably, one of the most widely valued social indicators is happiness. social researchers often use the term quality of life (qol) to describe what is commonly called "happiness". one of the leading pioneers of happiness research is ruut veenhoven (see #