Old age refers to ages nearing or surpassing the life expectancy of human beings, and is thus the end of the human life cycle. Euphemisms and terms for old people include, old people (worldwide usage), seniors (American usage), senior citizens (British and American usage), older adults (in the social sciences), the elderly , and elders (in a large number of cultures —including the cultures of aboriginal people).
Old people most often have limited regenerative abilities and are more susceptible to disease, syndromes, and sickness than younger adults. The organic process of ageing is called senescence,  the medical study of the ageing process is called gerontology,  and the study of diseases that afflict the elderly is called geriatrics.  The elderly additionally face additional social issues around retirement, loneliness, and ageism. 
The chronological age denoted as "old age" varies culturally and historically. Thus, old age is a "social construct" rather than a definite "biological stage". 
Definitions of old age include official definitions, popular definitions, sub-group definitions, and four dimensions as follows.
Old age comprises "the later part of life; the period of life after youth and middle age . . . , most of the time with reference to deterioration".  When old age begins can't be universally defined because it shifts according to the context. The United Nations has agreed that 60+ years might be most of the time denoted as old age  and this is the first attempt at an international definition of old age. Notwithstanding for its study of old age in Africa, the World Health Organization (WHO) set 50 as the beginning of old age. At the same time, the WHO recognised that the developing world most often defines old age, not by years, but by new roles, loss of previous roles, or inability to make active contribution to society. 
Most developed Western countries set the age of 60 to 65 for retirement. Being 60–65 years old is most of the time a requirement for fitting eligible for senior social programs.  Notwithstanding various countries and societies consider the onset of old age as anywhere from the mid-40s to the 70s.  The definitions of old age continues to change especially as life expectancy in developed countries has risen to beyond 80 years old. 
A Pew Research Center study of 2,929 Americans, age 18+, found that they hold quite different definitions of old age. Respondents up to their early 30's said that old age begins at 60, but respondents 65+ said 74. The average of all answers was 68. 
Most Britons define old age as starting at 59 according to a survey of 2,200 people in the UK. The under 25s reckon 54 as the beginning of old age. The 80+ define old age as starting at 68.  An Additional survey concluded that most Britons define the onset of old age as almost 70. Europeans on average set the start of old age at 62. 
Gerontologists have recognised the quite different conditions that people experience as they grow older within the years defined as old age. In developed countries, most people in their 60s and early 70s are still fit, active, and able to care for themselves. Notwithstanding after 75, they'll become increasingly frail, a condition marked by serious mental and physical debilitation. 
Therefore, rather than lumping together all people who have been defined as old, a few gerontologists have recognised the diversity of old age by defining sub-groups. One study distinguishes the young old (60 to 69), the middle old (70 to 79), and the quite old (80+).  An Additional study’s sub-grouping is young-old (65 to 74), middle-old (75–84), and oldest-old (85+).  A third sub-grouping is “young old” (65-74), “old” (74-84), and "old-old" (85+).  Delineating sub-groups in the 65+ population enables a more accurate portrayal of significant life changes. 
Two British scholars, Paul Higgs and Chris Gilleard, have added a “fourth age” sub-group. In British English, the “third age” is “the period in life of active retirement, following middle age”.  Higgs and Gilleard describe the fourth age as “an arena of inactive, unhealthy, unproductive, and ultimately unsuccessful ageing.” 
Dimensions of old age
Key Concepts in Social Gerontology lists four dimensions: chronological, biological, psychological, and social.  Wattis and Curran add a fifth dimension: developmental.  Chronological age might differ considerably from a person’s functional age. The distinguishing marks of old age normally occur in all five senses at different times and different rates for different persons.  In addition to chronological age, people can be considered old because of the additional dimensions of old age. For example, people might be considered old when they become grandparents or when they begin to do less or different work in retirement. 
Senior citizen is a common euphemism for an old person used in American English, and at times in British English. It implies or means that the person being referred to is retired.     This in turn most of the time implies or in fact means that the person is over the retirement age, which varies according to country. Synonyms include old age pensioner or pensioner in British English, and retiree and senior in American English. Some dictionaries describe widespread use of "senior citizen" for people over the age of 65. 
When defined in an official context, senior citizen is most often used for legal or policy-related reasons in determining who's eligible for certain benefits available to the age group.
It is used in general usage instead of traditional terms like old person , old-age pensioner , or elderly as a courtesy and to signify continuing relevance of and respect for this population group as " citizens " of society, of senior rank. 
The term was apparently coined in 1938 throughout a political campaign.  Famed caricaturist Al Hirschfeld claimed on several occasion that his father Isaac Hirschfeld invented the term 'senior citizen'.    It has come into widespread use in recent decades in legislation, commerce, and common speech. Especially in less formal contexts, it is most often abbreviated as "senior(s)", which is additionally used as an adjective.
In commerce, a few businesses offer customers of a certain age a " senior discount ". The age at which these discounts are available vary between 55, 60, 62 or 65, and additional criteria might additionally apply. Sometimes a special " senior discount card " or additional proof of age needs to be obtained and produced to show entitlement.
The age which qualifies for senior citizen status varies widely. In governmental contexts it is most of the time associated with an age at which pensions or medical benefits for the elderly become available. In commercial contexts, where it might serve as a marketing device to attract customers, the age is most often significantly lower. 
In Canada, the OASP (Old Age Security Pension) is available at 65 (gradually increasing to 67, starting in the years 2023-2029),  and the CPP (Canada Pension Plan) as early as age 60.
The AARP allows couples in which one spouse has reached the age of 50 to join, regardless of the age of the additional spouse.
Marks of old age
The distinguishing marks associated with old age comprise both physical and mental characteristics.  The marks of old age are so unlike the marks of middle age that it has been suggested that, as an individual transitions into old age, he/she might well be thought of as different persons “time-sharing” the same identity. 
These marks don't occur at the same chronological age for everyone. Also, they occur at different rates and order for different people.  Because each person is unique, marks of old age vary between people, even those of the same chronological age. 
A basic mark of old age that affects both body and mind is “slowness of behavior.”  This “slowing down principle” finds a correlation between advancing age and slowness of reaction and task performance, both physical and mental.  Notwithstanding a few studies have showns that the elderly constitute a happier age group than their younger adult counterparts. 
Physical marks of old age
Physical marks of old age include the following:
- Bone and joint. Old bones are marked by “thinning and shrinkage.” This results in a loss of height (about two inches by age 80), a stooping posture in a large number of people, and a greater susceptibility to bone and joint diseases like osteoarthritis and osteoporosis.  
- Chronic diseases. Most older persons have at least one chronic condition and a large number of have multiple conditions. In 2007-2009, the most frequently occurring conditions amongst older persons in the United States were uncontrolled hypertension (34%), diagnosed arthritis (50%), and heart disease (32%). 
- Chronic mucus hypersecretion (CMH) “defined as coughing and bringing up sputum. . . is a common respiratory symptom in elderly persons.” 
- Dental problems. Less saliva and less ability for oral hygiene in old age increases the chance of tooth decay and infection. 
- Digestive system. About forty percent of the time, old age is marked by digestive disorders like difficulty in swallowing, inability to eat enough and to absorb nutrition, constipation and bleeding. 
- Essential Tremor (ET) is an uncontrollable shaking in a part of the upper body. It is more common in the elderly and symptoms worsen with age. 
- Eyesight. Diminished eyesight makes it more difficult to read in low lighting and in smaller print. Speed with which an individual reads and the ability to locate objects might additionally be impaired. 
- Falls. Old age spells risk for injury from falls that might not cause injury to a younger person.  Every year, about one-third of those 65 years old and over half of those 80 years old fall.  Falls are the leading cause of injury and death for old people. 
- Gait change. Some aspects of gait normally change with old age. Gait velocity slows after age 70. Double stance time (i.e., time with both feet on the ground) additionally increases with age. Due to gait change, old people at times appear to be walking on ice. 
- Hair most of the time becomes thinner and grayer. 
- Hearing. By age 75 and older, 48 percent of men and 37 percent of women encounter impairments in hearing. Of the 26.7 million people over age 50 with a hearing impairment, only one in seven uses a hearing aid. 
- Hearts are less efficient in old age with a resulting loss of stamina. In addition, atherosclerosis can constrict blood flow. 
- Immune function. Less efficient immune function ( Immunosenescence) is a mark of old age. 
- Lungs expand less well; thus, they provide less oxygen. 
- Mobility impairment or loss. “Impairment in mobility affects fourteen percent of those between 65 and 74, but half of those over 85.”  Loss of mobility is common old people. This inability to get around has serious “social, psychological, and physical consequences”. 
- Pain afflicts old people at least twenty-five percent of the time, increasing with age up to eighty percent for those in nursing homes.  Most pains are rheumatological or malignant. 
- Sexuality remains important throughout the lifespan and the sexual expression of ‘typical, healthy older persons is a relatively neglected topic of research’.  Sexual attitudes and identity are established in early adulthood and change minimally over the course of a lifetime.  Notwithstanding sexual drive in both men and women decreases as they age.  That said, there's a growing body of research on people’s sexual behaviours and desires in later life that challenges the ‘asexual’ image of older adults. People aged 75–102 continue to experience sensuality and sexual pleasure.  Other known sexual behaviours in older age groups include sexual thoughts, fantasies and erotic dreams,  masturbation, oral sex, vaginal and anal intercourse. 
- Skin loses elasticity, becomes drier, and more lined and wrinkled. 
- Sleep trouble holds a chronic prevalence of over fifty percent in old age and results in daytime sleepiness.  In a study of 9,000 persons with a mean age of 74, only twelve percent reported no sleep complaints.  By age 65, deep sleep goes down to about 5%. 
- Taste buds diminish so that by age 80 taste buds are down to fifty percent of normal. Food becomes less appealing and nutrition can suffer.  
- Urinary incontinence is most often found in old age. 
- Voice. In old age, vocal cords weaken and vibrate more slowly. This results in a weakened, breathy voice that's at times called an “old person’s voice.” 
Mental marks of old age
Mental marks of old age include the following.
- Adaptable describes most people in their old age. In spite the stressfulness of old age, they're described as "agreeable" and "accepting." Notwithstanding old age dependence induces feelings of incompetence and worthlessness in a minority. 
- Caution marks old age. This antipathy toward "risk-taking" stems from the fact that old people have less to gain and more to lose by taking risks than younger people. 
- Depressed mood.  According to Cox, Abramson, Devine, and Hollon (2012), old age is a risk factor for depression caused by prejudice (i.e., “deprejudice”). When people are prejudiced against the elderly and then become old themselves, their anti-elderly prejudice turns inward, causing depression. “People with more negative age stereotypes will likely have higher rates of depression as they get older.”  Old age depression results in the over-65 population having the highest suicide rate.
- Fear of crime in old age, especially amongst the frail, at times weighs more heavily than concerns about finances or health and restricts what they do. The fear persists in spite of the fact that old people are victims of crime less most often than younger people. 
- Mental disorders afflict about fifteen percent of people aged 60+ according to estimates by the World Health Organization.  An Additional survey taken in 15 countries reported that mental disorders of adults interfered with their daily activities more than physical problems.
- Reduced mental and cognitive ability afflicts old age.  Memory loss is common in old age due to the decrease in speed of information being encoded, stored, and retrieved. It takes more time to learn new information.  Dementia is a general term for memory loss and additional intellectual abilities serious enough to interfere with daily life. Its prevalence increases in old age from about ten percent at age 65 to about fifty percent over age 85. Alzheimer's disease accounts for 50 to 80 percent of dementia cases. Demented behaviour can include wandering, physical aggression, verbal outbursts, depression, and psychosis. 
- Set in one’s ways describes a mind set of old age. A study of over 400 distinguished men and women in old age found a "preference for the routine." Explanations include old age’s toll on the "fluid intelligence" and the "more deeply entrenched" ways of the old.
Perceptions of old age
The literature regarding old age includes perceptions of old age from a middle-age perspective, from an old-age perspective, from society’s perspective, and from a simulated perspective.
Old age from a middle-age perspective
Numerous books by middle-age writers depict their perceptions of old people. One writer notices the change in his parents: they move slowly, they have lost strength, they repeat stories, their minds wander, and they fret. An Additional writer sees her aged parents and is bewildered: they refuse to follow her advice, they're obsessed with the past, they avoid risk, they live at a “glacial pace.” 
Other writers treat the perceptions of middle-age people regarding their own old age. In her The Denial of Aging , Dr. Muriel R. Gillick, a baby boomer, accuses her contemporaries of believing that by proper exercise and diet they can avoid the scourges of old age and proceed from middle age to death.  Studies find that a large number of people in the 55-75 range can postpone morbidity by practising healthy life styles. These discourses take part in a general idea of successful ageing. Notwithstanding at about age 80, all people experience similar morbidity.  Even with healthy life styles, most 85+ people will undergo extended “frailty and disability.” 
Old age from an old-age perspective
Early old age is a pleasant time: children are grown, retirement from work, time to pursue interests.  Many people are additionally willing to get involved in community and activist organizations to promote their well-being. In contrast, perceptions of old age by writers 80+ years old (“old age in the real meaning of the term) tend to be negative.
O Sovereign my Lord! Oldness has come; old age has descended. Feebleness has arrived; dotage is here anew. The heart sleeps wearily every day.
The eyes are weak, the ears are deaf, the strength is disappearing because of weariness of the heart and the mouth is silent and can't speak.
The heart is forgetful and can't recall yesterday. The bone suffers old age. God is become evil. All taste is gone. What old age does to men is evil in every respect. 
Minois comments that the scribe’s “cry shows that nothing has changed in the drama of decrepitude between the age of the Pharaoh and the atomic age” and “expresses all the anguish of old people in the past and the present.” 
Lillian Rubin, active in her 80s as an author, sociologist, and psychotherapist, opens her book 60 on Up: The Truth about Aging in America with “getting old sucks. It always has, it always will.” Dr. Rubin contrasts the “real old age” with the “rosy pictures” painted by middle-age writers. 
Writing at the age of 87, Mary C. Morrison delineates the heroism required by old age: to live through the disintegration of one’s own body or that of someone you love. Morrison concludes, “old age isn't for the fainthearted.”  In the book Life Beyond 85 Years , the 150 interviewees had to cope with physical and mental debilitation and with losses of loved ones. One interviewee described living in old age as “pure hell.” 
Old age from society’s perspective
Based on his survey of old age in history, Georges Minois concludes that “it is clear that always and everywhere youth has been preferred to old age.” In western thought, “old age is an evil, an infirmity and a dreary time of preparation for death.” Furthermore, death is most often preferred over “decrepitude, because death means deliverance.” 
“The problem of the ambiguity of old age has . . . been with us after the stage of primitive society; it was both the source of wisdom and of infirmity, experience and decrepitude, of prestige and suffering.”
In the Classical period of Greek and Roman cultures, old age was denigrated as a time of “decline and decrepitude.”  “Beauty and strength” were esteemed and old age was viewed as defiling and ugly. Old age was reckoned as one of the unanswerable “great mysteries” along with evil, pain, and suffering. “Decrepitude, which shrivels heroes, seemed worse than death.” 
The Medieval and Renaissance periods depicted old age as “cruel or weak.”
Old people from society's perspective
Historical periods reveal a mixed picture of the “position and status” of old people, but there has never been a “golden age of aging.” Studies have disproved the popular belief that in the past old people were venerated by society and cared for by their families.  Veneration for and antagonism toward the aged have coexisted in complex relationships throughout history.  “Old people were respected or despised, honoured or put to death according to circumstance.”
In ancient times, the quite few people who lived beyond 35 physically and mentally healthy, especially those of social status and wealth, were treated with “respect and awe.” In contrast, those who were frail were seen as a burden and ignored or in extreme cases killed. People were defined as “old” because of their inability to perform useful tasks rather than their years.
“The Olympians didn't like old people.” Their youth rebelled against the old, driving them off or killing them.
Although he was sceptical of the gods, Aristotle concurred in the dislike of old people. In his Ethics , he wrote that “old people are miserly; they don't acknowledge disinterested friendship; only seeking for what can satisfy their selfish needs.”
Medieval and Renaissance periods
For Thomas More, on the island of Utopia, when people are so old as to have “out-lived themselves” and are terminally ill, in pain, and a burden to everyone, the priests exhort them about choosing to die. The priests assure them that “they shall be happy after death.” If they choose to die, they end their lives by starvation or by taking opium. 
Antonio de Guevara ’s utopian nation “had a custom, not to live longer than sixty five years.” At that age, they practised self-immolation. Rather than condemn the practice, Bishop Guevara called it a “golden world” in which people “have overcome the natural appetite to desire to live.” 
In the Modern period, the “cultural status” of old people has declined in a large number of cultures. Joan Erikson observed that “aged individuals are most often ostracized, neglected, and overlooked; elders are seen no longer as bearers of wisdom but as embodiments of shame.”
Research on age-related attitudes consistently finds that negative attitudes exceed positive attitudes toward old people because of their looks and behavior. In his study Aging and Old Age , Posner discovers “resentment and disdain of older people” in American society.
Harvard University’s Implicit-association test measures implicit “attitudes and beliefs” about Young vis a vis Old.  Blind Spot: Hidden Biases of Good People , a book about the test, reports that eighty percent of Americans have an “automatic preference for the young over old” and that attitude is true worldwide. The young are “consistent in their negative attitude” toward the old.  Ageism documents that Americans generally have “little tolerance for older persons and quite few reservations about harbouring negative attitudes” about them. 
In 2014, a documentary film called The Age of Love used humour and poignant adventures of 30 seniors who attend a speed dating event for 70- to 90-year-olds, and discovered how the search for romance changes; or doesn't change; from a childhood sweetheart to older age. 
Old age from simulated perspective
Simone de Beauvoir wrote that “there is one form of experience that belongs only to those that are old – that of old age itself.”  Nevertheless, simulations of old age attempt to help younger people gain a few understanding.
- Sight: Wearing swimmer’s goggles with black paper pasted to lens with only a small hole to simulate tunnel vision,
- Hearing: Use ear plugs to dull the sound of people talking.
- Touch: Wearing thick gloves, button a shirt or buckle a belt.
- Dexterity: With tape around several fingers, unscrew a jar lid.
- Mobility and Balance: Carry packages in one hand while using a walker.
The Macklin Intergenerational Institute conducts Xtreme Aging workshops, as depicted in the The New York Times .  A condensed version was presented on NBC’s Today Show and is available online.  One exercise was to lay out 3 sets of 5 slips of paper. On set #1, write your 5 most enjoyed activities; on set #2, write your 5 most valued possessions; on set #3, write your 5 most loved people. Then “lose” them one by one, trying to feel each loss, until you have lost them all as happens in old age.
Old age frailty
Most people in the age range of 60-80 (the years of retirement and early old age), enjoy rich possibilities for a full life, but the condition of frailty distinguished by “bodily failure” and greater dependence becomes increasingly after that. In the United States, hospital discharge data from 2003-2011 shows that injury was the common reason for hospitalisation amongst patient aged 65+. 
Gerontologists note the lack of research regarding and the difficulty in defining frailty. Notwithstanding they add that physicians recognise frailty when they see it.
A group of geriatricians proposed a general definition of frailty as “a physical state of increased vulnerability to stressors  that results from decreased reserves and disregulation  in multiple physiological systems.”
Prevalence of frailty
Frailty is a common condition in later old age, but different definitions of frailty produce diverse assessments of prevalence. One study placed the incidence of frailty for ages 65+ at 10.7%.  An Additional study placed the incidence of frailty in age 65+ population at twenty-two percent for women and fifteen percent for men. A Canadian study illustrated how frailty increases with age and calculated the prevalence for 65+ as 22.4% and for 85+ as 43.7%. 
A worldwide study of “patterns of frailty” based on data from 20 nations found (a) a consistent correlation between frailty and age, (b) a higher frequency amongst women, and (c) more frailty in wealthier nations where greater support and medical care increases longevity. 
In Norway, a 20-year longitudinal study of 400 people found that bodily failure and greater dependence became prevalent in the 80+ years. The study calls these years the “fourth age” or “old age in the real meaning of the term.” Similarly, the “Berlin Aging Study” rated over-all functionality on four levels: good, medium, poor, and quite poor. People in their 70s were mostly rated good. In the 80-90 year range, the four levels of functionality were divided equally. By the 90-100 year range, sixty percent would be considered frail because of quite poor functionality and only five percent still possessed good functionality.
In the United States, the 85+ age group is the fastest growing, a group that's almost sure to face the “inevitable decrepitude” of survivors. (Frailty and decrepitude are synonyms.  )
Markers of frailty
Three unique markers of frailty have been proposed: (a) loss of any notion of invincibility, (b) loss of ability to do things essential to one’s care, and (c) loss of possibility for a subsequent life stage. 
Old age survivors on-average deteriorate from agility in their 65-80s to a period of frailty preceding death. This deterioration is gradual for a few and precipitous for others. Frailty is marked by an array of chronic physical and mental problems which means that frailty isn't treatable as a specific disease. These problems coupled with increased dependency in the basic activities of daily living (ADLs) required for personal care add emotional problems: depression and anxiety.  In sum, frailty has been depicted as a group of “complex issues,” distinct but “causally interconnected,” that most often include “comorbid diseases,”,  progressive weakness, stress, exhaustion, and depression. 
Misconceptions of frail people
Johnson and Barer did a pioneering study of Life Beyond 85 Years by interviews over a six-year period. In talking with 85+ year olds, they found a few popular conceptions about old age to be erroneous. Many studies of old age overlook the 85+ survivors so their conclusions don't apply. Such erroneous conceptions include (1) people in old age have a least one family member for support, (2) old age well-being requires social activity, and (3) “successful adaptation” to age-related changes demands a continuity of self-concept. In their interviews, Johnson and Barer found that twenty-four percent of the 85+ had no face-to-face family relationships; a large number of have outlived their families. Second, that contrary to popular notions, the interviews revealed that the reduced activity and socialising of the over 85s doesn't harm their well-being; they “welcome increased detachment.” Third, rather than a continuity of self-concept, as the interviewees faced new situations they changed their “cognitive and emotional processes” and reconstituted their “self–representation.” 
Care and costs
Frail people require a high level of care. Medical advances have made it possible to “postpone death” for years. This added time costs a large number of frail people “prolonged sickness, dependence, pain, and suffering.” 
According to a study by the Agency for Healthcare Research and Quality (AHRQ), the rate of ED visits was consistently highest amongst patients ages 85 years and older in 2006-2011 in the United States.  Additionally, patients aged 65+ had the highest percentage of hospital stays for adults with multiple chronic conditions but the second highest percentage of hospital costs in 2003-2014. 
Medical treatments in the final days aren't only economically costly, they're most often unnecessary, even harmful.  Nortin Hadler, M.D. warns against the tendency to medicalize and overtreat the frail.  In her Choosing Medical Care in Old Age , Muriel R. Gillick M.D. argues that appropriate medical treatment for the frail isn't the same as for the robust. The frail are vulnerable to “being tipped over” by any physical stress put on the system like medical interventions. 
Death and frailty
Old age, death, and frailty are linked because approximately half the deaths in old age are preceded by months or years of frailty, 
Older Adults' Views on Death is based on interviews with 109 people in the 70-90 age range, with a mean age of 80.7. Almost twenty percent of the people wanted to use whatever treatment that might postpone death. About the same number said that given a terminal illness, they would choose assisted suicide. Roughly half chose doing nothing except live day by day until death comes naturally without medical or additional intervention designed to prolong life. This choice was coupled with a desire to receive palliative care if needed. 
About half of older adults suffer multimorbidity, that is, they have three or more chronic conditions.  Medical advances have made it possible to “postpone death,” but in a large number of cases this postponement adds “prolonged sickness, dependence, pain, and suffering,” a time that's costly in social, psychological, economic terms. 
The longitudinal interviews of 150 age 85+ people summarised in Life Beyond 85 Years found “progressive terminal decline” in the year prior to death: constant fatigue, much sleep, detachment from people, things, and activities, simplified lives. Most of the interviewees didn't fear death; a few would welcome it. One person said, “living this long is pure hell.” Notwithstanding nearly everyone feared a long process of dying. Some wanted to die in their sleep; others wanted to die “on their feet.” 
The study of Older Adults' Views on Death found that the more frail people were, the more “pain, suffering, and struggles” they were enduring, the more likely they were to “accept and welcome” death as a release from their misery. Their fear about the process of dying was that it would prolong their distress. Besides being a release from misery, a few saw death as a way to reunion with departed loved ones. Others saw death as a way to free their caretakers from the burden of their care. 
Religiosity in old age
Mostly, at all times, old people have been more religious than young people.  At the same time, wide cultural variations exist.
In the United States, ninety percent of old age Hispanics view themselves as very, quite, or somewhat religious. The Pew Research Center’s study of black and white old people found that 62 percent of those in ages 65–74 and seventy percent in ages 75+ asserted that religion was “very important” to them. For all 65+ people, more women (76%) than men (53%) and more blacks (87%) than whites (63%) consider religion “very important” to them. This compares to 54 percent in the 30-49 age range. 
In a British 20-year longitudinal study, less than half of the old people surveyed said that religion was “very important” to them and one-fourth said they had become less religious in old age. The late-life rise in religiosity is stronger in Japan than in the United States, but in the Netherlands it is minimal.
In the practise of religion, a study of 60+ people found that twenty-five percent read the Bible every day and over forty percent look at religious TV. Pew Research found that in the age 65+ range, 75 percent of whites and 87 percent of blacks pray daily. 
Participation in organised religion isn't a good indicator of religiosity because transportation and health problems most often hinder participation.
In the industrialised countries, life expectancy and, thus, the old age population have increased consistently over the last decades.  In the United States the proportion of people aged 65 or older increased from four percent in 1900 to about twelve percent in 2000.  In 1900, only about 3 million of the nation's citizens were 65 or older (out of 76 million total American citizens). By 2000, the number of senior citizens had increased to about 35 million (of 280 million US citizens). Population experts estimate that more than 50 million Americans—about 17 percent of the population—will be 65 or older in 2020.  By 2050, it is projected that at least 400,000 Americans will be 100 or older. 
The number of old people is growing around the world mainly because of the post–World War II baby boom and increases in the provision and standards of health care.  By 2050, 33 percent of the developed world’s population and almost twenty percent of the less developed world’s population will be over 60 years old. 
The growing number of people living to their 80s and 90s in the developed world has strained public welfare systems and has additionally resulted in increased incidence of diseases like cancer and dementia that were rarely seen in premodern times. When the United States Social Security programme was created, persons older than 65 numbered only around five percent of the population and the average life expectancy of a 65-year-old in 1936 was approximately 5 years, while in 2011 it could most often range from 10–20 years. Other issues that can arise from an increasing population are growing demands for health care and an increase in demand for different types of services. 
Of the roughly 150,000 people who die each day across the globe, about two thirds—100,000 per day—die of age-related causes.  In industrialised nations, the proportion is much higher, reaching 90%. 
According to Erik Erikson ’s "Stages of Psychosocial Development”, the human personality is developed in a series of eight stages that take place from the time of birth and continue on throughout an individual’s complete life. He characterises old age as a period of "Integrity vs. Despair", throughout which a person focuses on reflecting back on his life. Those who're unsuccessful throughout this phase will feel that their life has been wasted and will experience a large number of regrets. The individual will be left with feelings of bitterness and despair. Those who feel proud of their accomplishments will feel a sense of integrity. Successfully completing this phase means looking back with few regrets and a general feeling of satisfaction. These individuals will attain wisdom, even when confronting death.    Coping is a quite important skill needed in the ageing process to move forward with life and not be 'stuck' in the past. The way a person adapts and copes, reflects his ageing process on a psycho-social level. 
For people in their 80s and 90s, Joan Erikson added a ninth stage in The Life Cycle Completed: Extended Version .  As she wrote, she added the ninth stage because the Integrity of the eighth stage imposes “a serious demand on the senses of elders” and the Wisdom of the eighth stage requires capacities that ninth stage elders “do not most of the time have.” 
Newman & Newman additionally proposed a ninth stage of life, Elderhood. Elderhood refers to those individuals who live past the life expectancy of their birth cohorts. There are two different types of people described in this stage of life. The "young old" are the healthy individuals who can function on their own without assistance and can complete their daily tasks independently. The "old old" are those who depend on specific services due to declining health or diseases. This period of life is characterised as a period of "immortality vs. extinction." Immortality is the belief that your life will go on past death, a few examples are an afterlife or living on through one's family. Extinction refers to feeling as if life has no purpose. 
Theories of old age
Social theories, or concepts,  propose explanations for the distinctive relationships between old people and their societies.
One of the theories is the Disengagement Theory proposed in 1961. This theory proposes that in old age a mutual disengagement between people and their society occurs in anticipation of death. By fitting disengaged from work and family responsibilities, according to this concept, people are enabled to enjoy their old age without stress. This theory has been subjected to the criticism that old age disengagement is neither natural, inevitable, nor beneficial.  Furthermore, disengaging from social ties in old age isn't across the board: unsatisfactory ties are dropped and satisfying ones kept. 
In opposition to the Disengagement Theory the Activity Theory of old age argues that disengagement in old age occurs not by desire, but by the barriers to social engagement imposed by society. This theory has been faulted for not factoring in psychological changes that occur in old age as shown by reduced activity even when available. It has additionally been found that happiness in old age isn't proportional to activity.
According to the Continuity Theory, in spite of the inevitable differences imposed by their old age, most people try to maintain continuity in personhood, activities, and relationships with their younger days.
Socioemotional Selectivity Theory additionally depicts how people maintain continuity in old age. The focus of this theory is continuity sustained by social networks, albeit networks narrowed by choice and by circumstances. The choice is for more harmonious relationships. The circumstances are loss of relationships by death and distance. 
Life expectancy by nation at birth in year 2011 ranged from 48 years to 82. 
In most parts of the world women live, on average, longer than men; even so, the disparities vary between 12 years in Russia to no difference or higher life expectancy for men in countries like Zimbabwe and Uganda. 
The number of elderly persons worldwide began to surge in the second half of the twentieth century. Up to that time (and still true in underdeveloped countries), five or less percent of the population was over 65. Few lived longer than their 70s and people who attained advanced age (i.e. their 80s) were rare enough to be a novelty and were revered as wise sages. The worldwide over 65 population in 1960 was one-third of the under 5 population. By 2013, the over 65 population had grown to equal the under 5 population. The over 65 population is projected to double the under five by 2050. 
Before the surge in the over 65 population, accidents and disease claimed a large number of people before they could attain old age, and health problems in those over 65 meant a quick death in most cases. If a person lived to an advanced age, it was due to genetic factors and/or a relatively easy lifestyle, after diseases of old age couldn't be treated before the twentieth century. 
Old age benefits
In 2003, the age at which a United States citizen became eligible for full Social Security benefits began to increase gradually, and will continue to do so until it reaches 67 in 2027. Full retirement age for Social Security benefits for people retiring in 2012 is age 66.  In the United Kingdom, the state pension age for men and women will rise to 66 in 2020 with further increases scheduled after that.” 
Originally, the purpose of old age pensions was to prevent elderly persons from being reduced to beggary, which is still common in a few underdeveloped countries, but growing life expectancies and older populations have brought into question the model under which pension systems were designed.  By 1990, the United States was spending 30 per cent of its budget on the elderly, compared with 2 per cent on education.  The dominant perception of the American old age population changed from “needy” and “worthy” to “powerful” and “greedy,” old people getting more than their share of the nation's resources.  Notwithstanding in 2011, using a Supplemental Poverty Measure (SPM), the old age American poverty rate was measured as 15.9%. 
Assistance: devices and personal
In the USA in 2008, 11 million people aged 65+ lived alone: 5 million or twenty-two percent of ages 65–74, 4 million or 34 percent of ages 75–84, and 2 million or 41 percent of ages 85+. The 2007 gender breakdown for all people 65+ was men nineteen percent and women 39%. 
Many new assistive devices made especially for the home have enabled more old people to care for themselves activities of daily living (ADL). Able Data  lists 40,000 assistive technology products in 20 categories.  Some examples of devices are a medical alert and safety system, shower seat (making it so the person doesn't get tired in the shower and fall), a bed cane (offering support to those with unsteadiness getting in and out of bed) and an ADL cuff (used with eating utensils for people with paralysis or hand weakness). 
A Swedish study found that at age 76, 46 percent of the subjects used assistive devices. When they reached age 86, 69 percent used them. The subjects were ambivalent regarding the use of the assistive devices: as “enablers” or as “disablers.”  People who view assistive devices as enabling greater independence accept and use them. Those who see them as symbols of disability reject them. 
Even with assistive devices as of 2006, 8½ million Americans needed personal assistance because of impaired basic activities of daily living (ADLs) required for personal care or impaired instrumental activities of daily living ( IADLs) required for independent living. Projections place this number at 21 million by 2030 when forty percent of Americans over 70 will need assistance.  There are a large number of options for such long term care to those who require it. There is the home care in which a family member, volunteer, or trained professional will aid the person in need and help with daily activities. An Additional option is community services which can provide the person with transportation, meal plans, or activities in senior centers. A third option is assisted living where 24-hour round-the-clock supervision is given with aid in eating, bathing, dressing, etc. A final option is a nursing home which provides professional nursing care.