In 2022, the population of Olivet was 72, a 1.41% increase year-by-year from 2021. Previously, in 2021, Olivet's population was 71, a decline of 1.39% compared to a population of 72 in 2020.
The median age in Olivet, KS is 68.0, as per 2021 ACS 5-Year Estimates. Of the total population, 17.19% were under the age of 15, 3.12% aged 15 to 29, 20.31% aged 30 to 64, 54.69% aged 65 to 84, and 4.69% were 85 years of age and older.