**3.1 Demographic dynamics of disabled persons by age**

Firstly, from a global view, the first population statistic to discuss is the WHO 2020 fact sheet on disability. It shows that there are about 1 billion people or 15% of the world's population who live with disabilities. The numbers are also increasing due to population growth, advances in medicine and healthcare, and the aging process [43]. Considering the global statistics, it is arguable that a substantial portion of every nation's population would be increasingly disabled.

Secondly, in the case of the USA, using the Center for Disease Control (CDC) fact sheet on disability [44], based on [45], the global statistic translates into 26% or 1 in 4 adults in USA having a disability. The fact sheet and original research report also show that, 2 in 5 adults aged 65 and above, have a disability [44, 45]. While a quarter of the adult population segment has disabilities in the USA, it is noteworthy that the ratio increases appreciably for retirees, pensioners, and senior citizens. This group would progress in impairment as they get older, thereby needing more accessibility.

Thirdly, analysis of 2019 data from the United States Census Bureau's (USCB) 1-year estimates, indicates that 41 million people or 12.7% of the US population have a disability [46]. While there seems to be a gap between [44–46], the census figures here refer to documented and non-hospitalized cases. Notwithstanding, there is a baseline of at least 41 million disabled persons who need access to independent living, including access to e-business services. The stated 12.7% of the population constitutes an appreciable market share that could be exploited. Furthermore, **Figure 1** derived from USCB data supports the phenomenon of a positive correlation between disabilities and aging.

**Figure 1.**

*Percentage of US population with a disability by age (derived from [46]).*

*Accessibility Experience Design (AxD): A Bi-directional Accessibility Perspective for e-Business… DOI: http://dx.doi.org/10.5772/intechopen.97488*

**Figure 1** shows that the proportion of people with disabilities increases with age. There is also the phenomenon of 'sudden leap' in the rate of increase at some stages, which occurs in the age ranges of 5–17, 35–64, and above 75. Perhaps the most significant trend is that by 75 years and above, about half of the population have a disability. This trend supports [44, 45]. Chronic medical conditions and aging process are major drivers of disability in the US. Chronic conditions increase with age. Since the percentage of people with a disability increases with age, it follows that a substantial portion of those in the range of 35–64 have disabilities, and they will progressively join the group of 65–74 and above 75. The collective volume of this population segment would be made up of people who are still working and those who are retired. In each case they would control substantial amounts of funds to make economic decisions, which could benefit e-business services.
