The rate at which growth must occur in a Harrod-Domar growth model if it is to be sustainable. If national income is Y, savings are S, and investment is I, savings are assumed to be a constant proportion of income so that S = sY. Investment is assumed to be given by an accelerator model, where investment is given by I = v(dY/dt), where t is time. For ex ante savings and investment to be equal requires that sY = v(dY/dt). This implies that the growth rate of Y must be w = (1/Y)(dY/dt) = s/v. This is the only rate at which equilibrium growth is possible, so long as the savings ratio s and the capital-output ratio v are taken as fixed.

• ordinary share
• organizational slack
• Organization for Economic Cooperation and Development
• Organization of Petroleum Exporting Countries
• organized labour
• organized sector
• origin
• oscillation
• oscillatory function
• other things being equal
• outcry, open
• outflow, capital
• outlier
• output
• output-capital ratio
• output effect
• output-input
• output method
• output per hour worked
• output per manhour
• outside money
• outsiders and insiders
• outsourcing
• over-capacity working
• overdraft