Some things we can predict about the future, while others we can't. One thing we can predict is that the world in general countries has an aging population. This is significant both in terms of pure numbes and as a percentage of the population as an aging population typically drives up health and other social service costs. What will be the impacts in different countries, however, will vary as in some countries immigration of working-age adults will help offset the aging population. Also, it is too soon how societies will adapt to their aging populations. As an example, in some countries extended families may help provide care for their aging populations. In other countries and societies, however, the elderly may have to postpose retirement and remain in the work force longer. An aging population will also have a significant effect on housing as the elderly will typically look to move to smaller, accessible homes. This will potentially have the effect of greating an over-supply of large single-family homes as the elderly retire. Finally, one of the greatest impacts of an aging population will be the requirement that governments such as the U.S. government fund social security and retirement benefits as the baby boom generation reaches retirement age. At a time when the world is in an economic recession and the U.S. and other governments have run up record deficits, this will perhaps be the greatest problem posed by an aging population.