It also demands a sense of security. Indeed, studies show that anxiety lowers human well being. Think of a poor farmer who does not have access to irrigation projects. His family's survival depends on getting enough rain for his crops. But this vulnerability goes way beyond the seasons of nature.
Survey data show that monthly incomes fluctuate more than annual incomes.
This is caused by the ebbs and flows of the economy. A craftsman may have to starve if the demand for his craft products falls suddenly. Simply comparing average monthly incomes cannot reveal this vulnerability. Consider a family with a monthly income slightly above the official poverty line. That sum, however, is only an average.