How do we define old age?

The only constant is change. As we change, we have to make many adjustments, and these may be unsettling. So, I started thinking about age and wondered how we in the world, define old age.

From the United Nations I found this: “Most developed world countries have accepted the chronological age of 65 years as a definition of 'elderly' or older person, but like many westernized concepts, this does not adapt well to the situation in Africa. While this definition is somewhat arbitrary, it is many times associated with the age at which one can begin to receive pension benefits. At the moment, there is no United Nations standard numerical criterion, but the UN agreed cut-off is 60+ years to refer to the older population.”

Although there are commonly used definitions of old age, it has changed over the years as far back as 1875, in Britain, the Friendly Societies Act, enacted the definition of old age as, "any age after 50"

In many parts of the developing world, the chronological time has little or no importance in the meaning of old age. Other socially constructed meanings of age are more significant such as the roles assigned to older people; in some cases, it is the loss of roles accompanying physical decline, which is significant in defining old age.

This transition from a contributing member of society to a non-contributing member became the basis for the definition of old age which occurred between the ages of 45 and 55 years for women and between the ages of 55 and 75 years for men.

In contrast to the chronological milestones which mark life stages in the developed world, old age in many developing countries is seen to begin at the point when an active contribution is no longer possible.

Study results published in 1980 provides a basis for a definition of old age in developing countries. This international anthropological study was conducted in the late 1970's and included multiple areas in Africa. Definitions fell into three main categories:

1. Chronology

2. Change in social role (i.e. change in work patterns, adult status of children and menopause)

3. Change in capabilities (i.e. invalid status, senility and change in physical characteristics).

Results from this cultural analysis of old age suggested that change in social role is the predominant means of defining old age.

From Wikipedia came this: A Pew Research Center study of 2,929 Americans, age 18+, found that they hold very different definitions of old age. Respondents up to early 30's said that old age begins at 60, but respondents 65+ said 74

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. Another 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.

I define old age as anyone who is 10 years older than me. How do you define old age?