Also the older population are living very long and there is a labor shortage and big burden on the young as many Japanese are not getting married or having children. There is a big demographic problem at present in Japan that needs to be addressed if the rest of the economic issues need to get solved. The same with Greece, you have too much of the population living in the cities so infrastructure in the small towns and villages and agriculture along with small manufacturing has to blossom again.
A lot of discussions have been ongoing on the Japanese demographic crisis. But still, I feel that the demography there isn't as bad as some people would like to project. The birth rates are really low, but recently Japan overtook Germany in that parameter. This is a big achievement, considering that Japan is a homogenous society with uniform birth rate across the regions, and Germany is a multicultural society with a large high-fertility immigrant population. Also, the health sector in Japan is quite impressive, making it possible for retirement age to be extended considerably.
