Sectoral Economic Efficiency and Economic Growth Across Development Stages: Theory, Measurement, and International Panel Evidence

This paper examines which economic sectors produce the highest return relative to cost, a central but still unresolved question in development economics and macroeconomic policy. To address this, it introduces the Sectoral Economic Efficiency Index (SEEI), a multidimensional measure that combines benefits such as GDP growth, job creation, labor productivity, exports, and innovation against costs including capital requirements, public support, environmental burden, duration, and infrastructure needs. Building on SEEI, the paper develops the Sectoral Efficiency Frontier Theory (SEFT), which argues that the most efficient investment priorities are not fixed across countries, but depend on development stage, institutional capacity, and inter-sectoral linkages. It also proposes the Dynamic Cost-Benefit Productivity Index (DCBPI) to capture risk-adjusted productivity across short-, medium-, and long-term horizons. The analysis uses a balanced panel of 127 countries from 1995 to 2023, drawing on data from the World Bank, IMF, OECD, ILO, UNIDO, and WIPO. Using Fixed Effects, Random Effects, System GMM, Difference-in-Differences, and Quantile Regression models, the paper finds strong support for SEFT. ICT and advanced business services show the highest efficiency in high-income economies, while advanced manufacturing and industrial upgrading are more efficient in upper-middle-income economies. Infrastructure investment is consistently strong in the short run across all stages, while R&D, green energy, and human capital formation dominate in the long run, with DCBPI values roughly 2.4 to 3.1 times higher than short-run alternatives. These findings suggest a phased sectoral strategy for growth and offer practical guidance for industrial policy under fiscal constraints.