Structural Transformation in Nigerian Agriculture: A Decomposition Analysis of Sources of Agricultural Growth Across Geopolitical Zones

Understanding the sources of agricultural growth, whether driven by technical progress, resource reallocation, structural change, or factor accumulation, is fundamental for designing strategies that sustain long-term sectoral and economy-wide development in Nigeria. Existing growth accounting studies for Nigerian agriculture are methodologically limited and do not capture cross-zone heterogeneity in growth drivers. This study conducts a comprehensive decomposition analysis of agricultural output growth across Nigeria's six geopolitical zones from 2005 to 2024 using a newly constructed state-level panel dataset from National Bureau of Statistics, FAO country data, and state ministry reports. A Divisia index decomposition framework separates output growth into contributions from land expansion, labour intensification, capital deepening, intermediate input increase, and total factor productivity growth. A second-stage regression analyses the structural correlates of the total factor productivity component. Results indicate that output growth has been predominantly input-driven in five of six zones, with total factor productivity contributing less than 25 percent of growth in the South East, North West, and North East zones. The North Central zone, driven by irrigation expansion and improved seed adoption, recorded the highest total factor productivity contribution at 38 percent. Structural transformation out of subsistence and into commercial farm systems is documented in the South West zone and is positively associated with improved road infrastructure density and agricultural development programme coverage intensity. The study provides original empirical evidence on the transformation frontier of Nigerian agriculture and recommends a reorientation of agricultural investment from input subsidies toward research, extension, and market infrastructure. Keywords: structural transformation, agricultural growth, decomposition, total factor productivity, Nigeria