While it is sad to believe who can not grow forever, atleast in terms of economics, but it is hard reality. Ruchir Sharma offer his two-cents. His contention is that, at the time of Reagan productivity and population growth was both 1.75%, hence US could grow at 3.5%. With population growth declining and productivity at just .75% its hard to achieve purported 3-4% growth. This is the new normal and we all have to adjust to it.