<P> However, population aging also increases some categories of expenditure, including some met from public finances . The largest area of expenditure in many countries is now health care, whose cost is likely to increase dramatically as populations age . This would present governments with hard choices between higher taxes, including a possible reweighing of tax from earnings to consumption, and a reduced government role in providing health care . However, recent studies in some countries demonstrate the dramatic rising costs of health care are more attributable to rising drug and doctor costs, and higher use of diagnostic testing by all age groups, and not to the aging population as is often claimed . </P> <P> The second - largest expenditure of most governments is education and these expenses will tend to fall with an aging population, especially as fewer young people would probably continue into tertiary education as they would be in demand as part of the work force . </P> <P> Social security systems have also begun to experience problems . Earlier defined benefit pension systems are experiencing sustainability problems due to the increased longevity . The extension of the pension period was not paired with an extension of the active labour period or a rise in pension contributions, resulting in a decline of replacement ratios . </P> <P> The expectation of continuing population aging prompts questions about welfare states' capacity to meet the needs of their population . In the early 2000s, the World's Health Organization set up guidelines to encourage "active aging" and to help local governments address the challenges of an aging population (Global Age - Friendly Cities) with regard to urbanization, housing, transportation, social participation, health services, etc . Local governments are well positioned to meet the needs of local, smaller populations, but as their resources vary from one to another (e.g. property taxes, the existence of community organizations), the greater responsibility on local governments is likely to increase inequalities . In Canada, the most fortunate and healthier elders tend to live in more prosperous cities offering a wide range of services, whereas the less fortunate don't have access to the same level of resources . Private residences for the elderly also provide many services related to health and social participation (e.g. pharmacy, group activities and events) on site; however they are not accessible to the less fortunate. . Also, the Environmental gerontology indicates the importance of the environment in active aging . In fact, promoting good environments (natural, built, social) in aging can improve health and quality of life, as well as reduce the problems of disability and dependence, and, in general, social spending and health spending. . </P>

Which country is experiencing the most rapid rate of population aging in the world