Fertility Rate
A sustainable population requires a fertility rate of around two or slightly more, on average, as suggested by mathematics. A lower fertility rate implies that children are seen as less useful. When subscribing to a product, its utility normally increases over time, accelerating its value and potentially reducing its cost. This principle can be similarly applied to children, but with a negative cost implication. The negative price means, if you do not sell it, nothing would be bought from you and if you sell, it will be definitely bought....