The estimated production function for South Africa has proven to be of Cobb-Douglas
technology (Du Toit, 1999) and is represented by the following expression:
(1)
Y =AtKtαNtβ
with
Yt = actual gross domestic product at factor cost
At = unobservable technical progress or technology (including factor productivity)
Nt = actual employment
Kt = actual capital stock
α = capital share parameter
β = labour share parameter
(α + β) is restricted to 1; assuming constant returns to scale technology
Potential output is determined by substituting trend total factor productivity (A* ), actual capital
stock2 (K) and potential employment (N * ) back into the estimated production function.
In this analysis the measure of potential employment is defined as the level of labour resources
that might be employed without resulting in additional inflation. This amounts to adjusting the
actual labour input used in the estimated production function for the gap between actual
unemployment and the estimated non-accelerating wage rate of unemployment (NAWRU).
However, should “potential” be defined as the maximum output level, then potential
employment would be represented by the entire labour force of working age (economically active
population), thereby assuming that everyone of working age (excluding those voluntarily
unemployed) has the potential and necessary skills to fill the available job openings. Should
Since our focus is the labour market, and not the capital market.