Today someone told me about two articles on The Economics website. <http://www.economist.com/node/17492860?story_id=17492860&CFID=154073501&CFTOKEN=94106062>. The title is The Future of Japan, The Japan Syndrome. And the second article <http://www.economist.com/node/17522568> is A special report on Japan, Into the unknown.
They both tackle the problem of aging Japan. I would recommend you reading both of these.
Aging is also a huge issue in Japanese churches. The number of older pastors is creating a ministry vacuum as younger people fail to enter the ministry in sufficient numbers to take over from the older pastors.
Many churches have a disproportionate number of older people and struggle to reach out to younger people. This is true in many cultures, but especially in Japan the percentage of older people is higher than any other country.
And the third issue is how to reach out to older people with the gospel. We often hear that Japanese young people are much more open to the gospel than older people. Perhaps part of the reason is that we tend to spend more energy reaching out to the younger people. Christian Senior Citizen Centers, retirement facilities and nursing homes are increasing, and need to increase even more.