Competition and Market Concentration in Tamarind Processing and Marketing: Insights from the Herfindahl-Hirschman Index and Concentration Ratio.

Abstract

This study examines the market structure, level of competition, and concentration among tamarind processors and marketers in Kano, Kaduna, and Nasarawa States of northern Nigeria. Using primary data from 2025 and employing the Herfindahl-Hirschman Index (HHI), the study assesses the distribution of market shares and the extent of dominance among participants in the tamarind value chain. Results show that the processing segment is highly competitive and atomistic across all states, with extremely low HHI values of 0.0000329 (Kano), 0.0000289 (Kaduna), and 0.0000196 (Nasarawa). The marketing segment demonstrates varying levels of competition, with Kano showing moderate concentration (HHI = 0.0022862), while Kaduna (0.0006102) and Nasarawa (0.0001246) exhibit low concentration and high competitiveness. The findings highlight a vibrant but fragmented industry characterized by low market power, limited economies of scale, and significant opportunities for new entrants. The joint application of CR₄ and HHI reveals a tight oligopolistic market structure in Kano State and highly concentrated, near-monopolistic structures in Kaduna and Nasarawa States, indicating significant market dominance by a few firms in tamarind processing.