Sectoral Elasticity of Substitution and Returns to Scale in South Africa

South African Journal of Economics Vol. 76:S2 August 2008

Elasticity of substitution and returns to scale are estimated on a sectoral basis for South Africa using panel-based generalised least square procedure. Apart from sectoral differences in terms of elasticity of substitution, the study found that elasticity of substitution is below unity in all of the sectors. Most of the sectors studied are found to have increasing returns to scale in production. The study further explores the implications of elasticity of factor substitution and returns to scale on growth and employment creation. It is argued that a greater number of jobs can be created from growth of sectors with constant or decreasing returns to scale than from the same level of output growth generated by sectors with increasing returns to scale. This is the case when the employment-creating potential of the same amount of additional output is compared in all the sectors examined. By virtue of scale economies, a sector like finance, insurance, real estate and business services generates more output with less proportional increase in inputs, which means growth in this sector may not have the desired impact on job creation. However, given the sector’s large share (20%) of the country’s total output and employment, it may generate more jobs, even if sectors like utilities and construction experience the same level of output growth. Given its importance for growth and employment, the study recommends further investigation into the reasons why elasticity of substitution is lower in sectors like utilities, mining and trade, catering and accommodation services.