Statistical Forecasting of Population Growth in Abuja FCT Using Census-Based Projection Models

Abuja, Nigeria's Federal Capital Territory, has experienced among the fastest urban population growth rates in Africa over the past two decades, creating persistent pressure on infrastructure, housing, and public services that evidence-based population projection can help anticipate and plan for. This study applies statistical population projection models to forecast FCT population growth from 2023 to 2035. Baseline population data from the 2006 Census were combined with 2016 and 2023 intercensal estimates from the National Population Commission. Three projection models were applied: geometric growth, exponential growth, and the component cohort survival method using age-sex specific survival ratios. Model performance was evaluated by comparing back-projections to known intercensal estimates. The geometric growth model yielded a FCT population of 4.1 million in 2023, consistent with NPC estimates. The exponential model projected 6.8 million by 2030 and 9.2 million by 2035 under sustained high growth. The component model projected 7.4 million by 2030 and 9.8 million by 2035 under medium fertility assumptions. Inter-model variation widened substantially beyond 2030, reflecting demographic uncertainty. Sensitivity analysis showed that fertility rate assumptions drove the widest projection range. The study recommends FCT planning authorities adopt probabilistic population projection intervals rather than point estimates to reflect demographic uncertainty in infrastructure investment planning. Keywords: population projection, FCT Abuja, census-based model, demographic statistics, urban growth