Recently the mummified corpse of a man who, were he still alive, would be 111 years old and Tokyo's oldest man, was discovered. His immediate family had apparently followed his orders to leave him alone in his room so that he could "become a living Buddha"...in the style of legendary monks, apparently by starving to death or dying of dehydration, and he's thought to have died 30-odd years ago. Until he was finally found, the ward officials had believed him to be their oldest living resident.
This was followed shortly by the realization that a woman who is--or would be--113, and Tokyo's oldest resident, can not be located. Her daughter, with whom she is registered as living, apparently thought she was living with a younger brother in another city. The daughter has had no contact with either relative for years, and a check of the brother's address has shown it to be a vacant lot on its way to becoming part of a new road. The last news I heard about this case was that the police had finally located the brother, who informed them that his mother had died years ago. The news story I heard implied that further investigation was proceeding.
These two cases caught so much media attention that not only investigative reporters but even the various ward and city offices involved have begun to try to determine the whereabouts of the elderly...at least those 100 or over. As I write this, the total nationwide whose location (or even current existence) cannot be verified has risen to 56. Tokyo had 5 so far, Osaka 18, Hokkaido and a couple of other prefectures 4 each, and several other prefectures one each, the last time I saw a breakdown.
I imagine that the number will rise, across the nation, as people are belatedly checked on more aggressively. There are (probably) over 40,000 centenarians in Japan, after all. If the confirmation parameters were expanded to include those over, say, 80, the total would no doubt be surprisingly high. If all those over 65, the basic starting age for pensioners, were investigated, the total of citizens for whose location or current condition (i.e., whether they are still alive) cannot be confirmed would probably be astounding.
In some countries, this wouldn't be too surprising. Not all countries, or cultures, are highly focused on actively keeping track of their citizens' whereabouts and health conditions. At the risk of sounding cynical, I'd say that this is particularly true of those citizens who are old enough not to be taxpayers any more. To be fair, many societies are not willing to put up with too much government checking into their lives. Not a few people resent even regular census efforts as an invasion of privacy and an unacceptable level of meddling in their lives. Many countries lack the resources even if they have the desire.
Japan, however, requires every resident to register with his or her local government office, and to update the records when they move. Citizens need a current copy of the juminhyo (residence registration) for all sorts of things, such as buying or selling or renting property, acquiring a driver's license, making credit or other contracts, applying for jobs, buying a vehicle, and pretty much anything else that requires more than very simple proof of identity.
For foreign residents, some of them centenarians who are also "missing", this essential document's purpose is served by the infamous gaikokujin toroku shomeisho (proof of foreigner's registration), which we are all required to carry at all times. A document verifying the registration can be acquired from one's local government office and used in place of the juminhyo.
Note that the juminhyo, or its foreigner equivalent, can only be procured from the local government office in which one is registered. If you move to another administrative area (generally speaking, to another ward or city), you are obligated to transfer your residence registration to the new locale.
So, theoretically, the government has a record of where each of its residents resides. There are further records (family registers) by household and/or family, with a smaller version for individuals, wherein births, deaths, and marriages are recorded along with information about who the head of the household is, and who has left the household/family. Copies of these rather more detailed records are also sometimes required by, for example, prospective employers, or for registering a marriage or the paternity of a child.
In addition, many if not most local police forces have traditionally made rather concerted efforts to canvass neighborhoods to determine who lives where. Pretty much every time I've moved in Japan (about a dozen times), a local cop appeared at my door within a week or so, politely inquiring about who I am and whom I'm living with. The downside of this is that the police may know more about you than some people might be comfortable with, the upside is that visitors who get lost trying to find your house in Japan's semi-chaotic house numbering system can ask at the local police box with a strong chance of getting precise directions, sometimes even a police escort. If a catastrophe befalls one's house--say a fire, earthquake, or meteor strike--the police have a pretty good idea of at least who might have been expected to be there when the disaster struck.
With all this interest in and record-keeping for residents' locations, it has become a (belated, in my opinion) source of surprise that the government can't locate so many of its senior citizens...or even confirm whether they're alive or dead. It has also become a source of embarrassment for the local governments who are supposed to be keeping track of their residents (not least because there are sometimes issues with where pension payments have been going, and who might have been spending them).
Of course, if you don't do anything that requires a copy of your residence documents, you're pretty much "off the radar".
The reasons I've seen given so far by government officials for why they've lost track of their citizens have centered on right-to-privacy issues. This may lead to a change in the law governing protection of personal information. In at least some cases, government workers who have inquired about the elderly in their areas have been turned away by relatives, or been unwilling to go beyond pressing ineffectually at unanswered doorbells. In more urban areas, the decades-long trend of people not really knowing much if anything about their neighbors has contributed to the difficulty of getting information about unresponsive residents.
Nobody has mentioned it yet, at least in the national media that I've seen, but there may also be a problem with a lack of coordination between government departments: most people's deaths are reported to the local government office, either by relatives or by the police, and I suspect that the reports haven't been circulated to everyone who ought to know, so that one department may know that someone has passed away, while another department in the same office may still have them on their resident rolls. Of course, this may not be the case, and as I say I haven't heard it mentioned, but it wouldn't surprise me much.
I imagine that at least some of the people may have quietly disappeared--with or without the knowledge of and/or reports from any relatives--and become homeless, or wandered off into the woods, either way perhaps eventually to have become unidentified corpses. If there's no landlord worrying about unpaid rent, and no concerned relatives or friends, that's not at all inconceivable. There are even more disappearances--95,989 in 2004, for example--than suicides in Japan every year (about 30,000), and I don't think that anyone is systematically correlating disappearances, found missing people, and unidentified corpses. As far as I can determine, there doesn't even seem to be any systematic correlation between disappearances and suicides, at least at a national level.
I doubt that anything that looks like a natural death of someone not immediately identifiable inspires much effort from the police to determine who they might have been, unless there's a local missing person report, and probably one that's pretty recent. I suppose that there is, unfortunately, not much reason for the police to spend limited resources on them if nobody else seems to be concerned.
When the annual national holiday, Respect for the Aged Day, comes around, there are always plenty of human interest stories in the news about people who have managed to live to 100 or beyond. Reporters interview them, local government people visit them and present them with small gifts, and so on. Some of them may even become media celebrities, for a while at least.
In Japan, as in most of Asia, in principle the elderly have traditionally been respected, even revered, for their experience and presumed wisdom.
It's a pity that nobody seems to know where so many of them are, or indeed even whether they're alive.