27.99% of the population of Sumba Tengah Regency in 2023 were aged 0-14 years.

According to 2023 data from the Central Statistics Agency (BPS), 57,311 or approximately 63.38% of the population in Sumba Tengah Regency are in the productive age group (15-59 years old). Meanwhile, 27.99% of the total population, or approximately 25,304, are children (aged 0-14 years), and another 8.63% are aged over 60 years.

The population of Sumba Tengah Regency was recorded at 90,418 as of 2023. This figure is higher than in 2021 and December 2020. Compared to the previous five years, the Compound Annual Growth Rate (CAGR) of this region is higher. The growth over the last five years was recorded at 4.72%.

In terms of nominal population compared to other regions in East Nusa Tenggara Province, this regency/city ranks 22nd. When grouped by island, it ranks 41st.

The following is the population by age group in Sumba Tengah Regency as of December 2023, sourced from the publication of the Central Statistics Agency (BPS):

* Age 0-4 years: 7.47 thousand people (8.27%)
* Age 5-9 years: 8.58 thousand people (9.49%)
* Age 10-14 years: 9.25 thousand people (10.23%)
* Age 15-19 years: 10.9 thousand people (12.06%)

* Age 20-24 years: 9.48 thousand people (10.49%)
* Age 25-29 years: 7.36 thousand people (8.14%)
* Age 30-34 years: 6 thousand people (6.64%)
* Age 35-39 years: 6.21 thousand people (6.87%)
* Age 40-44 years: 5.36 thousand people (5.92%)
* Age 45-49 years: 4.74 thousand people (5.25%)
* Age 50-54 years: 3.98 thousand people (4.4%)
* Age 55-59 years: 3.27 thousand people (3.62%)
* Age 60-64 years: 2.57 thousand people (2.84%)
* Age 65-69 years: 2 thousand people (2.22%)
* Age 70-74 years: 1.36 thousand people (1.5%)
* Age 75 years and over: 1.87 thousand people (2.07%)