Age structure is the distribution of people across various age categories. In Nyeri County, the age pyramid allows us to visualize how people of different age groups are distributed by sex.
In 2024, Nyeri County had a population of 844,000, up from a population of 759,164 in 2019.[1]
Of these, 374,288 were males, 384,845 were females, and 31 were intersex. Females comprised 50.6% of the population in Nyeri County in 2019.[2]
The pyramid below shows the age structure of Nyeri County by sex.
Nyeri County has slightly more males than females in early childhood, but that changes in adulthood.
Nyeri has a normal sex ratio at birth of 102 males for every 100 females, which explains the slightly higher number of males than females in early childhood.[3] For instance, between ages 0 – 4, there were 37,016 male children and 36,082 females.
Females become the majority from 25 years onward, consistently throughout adulthood and old age. We can attribute this to the disproportionately higher mortality rate in males than females, leading to a female bias in older age groups.
Furthermore, Females in Nyeri have a higher life expectancy than males. At birth, females in Nyeri have a life expectancy of 75.8 years, while males have a life expectancy of 66.4 years.[4]
Even in old age, females are expected to live longer than males, leading to a higher number of females. Life expectancy at age 60 among males in Nyeri was 16.3 years, compared to females, who are expected to live for an additional 22.2 years.
The life expectancy at age 70 further maintains the trend, with men expected to live for an additional 10.3 years and women 14 years.
Females in Nyeri have a lower adult and old age mortality compared to males.
Another reason why there are more females than males in older age groups is that fewer women than men die.
For instance, among men who reach age 15 in Nyeri, 464.7 per 1000 males die before their 60th birthday.[5]
On the other hand, the adult mortality among females in Nyeri is lower, with 77 per 1000 people expected to die before age 60.[6]
Similarly, women have a lower old-age mortality in Nyeri than males. Among males who reach the age of 60, around 749 of every 1000 do not reach age 80. On the contrary, in females, only 496.6 per 1000 are not expected to reach 80 years of age.
Nyeri has a lower child dependency ratio than the national average
From the pyramid above, we see that the difference between the number of children in Nyeri and that of adults is not as dramatic as we see in other parts of the country. In Kenya, the pyramid is broad at the bottom and narrow significantly at the centre and top.
In Nyeri, the pyramid is broad at the bottom and only narrows slightly toward the top, with a bulge at the center. This suggests that, unlike other counties, Nyeri has a slightly large number of working-age adults, contributing to its lower child dependency ratio.
The child dependency ratio is the number of children aged 0- 14 for every 100 working-age adults aged 15 – 64. In Nyeri, the child dependency ratio is 47.5%, meaning there are 47.5 children for every 100 working-age adults.[7]
The national average is 68.3%, while in some counties, the ratio is significantly higher. In Mandera, the child dependency ratio is 128.7%, meaning there are 129 children for every 100 working-age adults.
Overall, a lower child dependency ratio in Nyeri means working-age adults have fewer children to support, which improves their economic well-being.
Nyeri has a higher old-age dependency ratio than the national average
Nyeri has the highest life expectancy in Kenya, with women expected to live 75.8 years and men 66.4 years. As a result, more people reach old age than in the rest of the country.
The old-age dependency ratio in Nyeri is 12.8%, meaning there are around thirteen old people aged 65 and above in the county for every 100 working-age people. The national old-age dependency ratio is 6.9% or seven people for every 100 working-age people.
The country's old-age dependency ratio is low and should not be a significant problem. In Nyeri County, the working-age population should be able to support the elderly without significant problems.
See Also
References
[1] 2019 Kenya Population and Housing Census: Analytical report on population projections. Vol. XVI.
[2] 2019 Kenya Population and Housing Census: Population by county and sub-county. Vol. I.
[3] 2019 Kenya Population and Housing Census: Analytical Report on Mortality. Vol. VII.
[4] 2019 Kenya Population and Housing Census: Analytical Report on Mortality. Vol. VII.
[5] NOTE from KNBS: “Caution should be taken for the high male adult mortality in Central Kenya. This may be due to the high number of respondents from single mothers who reported their fathers to be dead and that was not so, or reported to not know whether the father is alive or not.”
[6] 2019 Kenya Population and Housing Census: Analytical Report on Mortality. Vol. VII.
[7] 2019 Kenya Population and Housing Census: Analytical Report on Population Dynamics. Vol. VIII.
