Write consumption per worker as a function of the capital stock in steady-state. Ans. The change in capital stock in the solow model is given by: a.Δ k = σ f ( k ) − δ k. Enhance your law practice, build community, and promote justice with the American Immigration Lawyers Association. Become A Member Today. As the capital stock increases, the additional investment tails off but the additional depreciation does not, so at some point sYt equals δK.