Introducing the "oldest old".

The mounting numbers of the very old--their percentage of the population will double in the next 15 years--is so new a phenomenon that there is little in historical experience to help in interpreting it. Not only are the older living longer, but they are also growing older in markedly different ways from their predecessors. The work at hand, still partial and tentative, indicates that the oldest old can no longer remain invisible in the economy, the polity, the health care system, or the statistical records.