factors (described in the capital sector) are the same, then 1 unit of the effective capital when is 1.0 the effective output is 0.95 (= 1.0 * ( 1 - 0.05)). So, when nrfr is 0.5, the effective output is 0.90 (= 1.0 * (1 - 0.10)). Another useful way to look at this equation is to reverse it and see how much effective capital is required to get 1 unit of effective output (i.e. effective_output / (1 - fcaor) = effective_capital). So, when nrfr is 1.0, the effective capital required for 1 unit of effective output is 1.053 (=1.0/(1-0.05)), and when nrfr is 0.3, the effective capital required is 2 (=1.0/(1-0.5)). Lastly, looking at the relative cost is required for obtaining the resources. This is based on the fact that it requires 1/19th of a unit of effective capital extra when the nrfr is 1.0. So, (effective capital required - 1.0) / (1 / 19) will give the relative cost of obtaining the resources compared to the cost of obtaining them when nrfr was 1.0. For example, when nrfr is 0.3, the effective capital required is 2.0, and 1.0 of that is for obtaining resources. So, the cost of obtaining the resources is (2.0 - 1.0) / ( 1 / 19) or 1.0*19 or 19 times the cost when nrfr was 1.0. Here is a table showing these calculations for all the values: Consumption of Nonrenewable Resources The World3 model does not directly link industrial output to resource utilization. Instead, the industrial output per capita is calculated, which is then used to determine resource usage per capita. This is then multiplied by the total population to determine the total resource consumption. Per capita resource utilization multiplier (PCRUM) and Industrial Output per Capita (IOPC) References Models of Doom, A Critique of the Limits to Growth, edited by H.S.D. Cole, Christoper Freeman, Marie Jahoda, and K.L.R. Pavitt. 1973 (Especially Chapter 3: The Non-renewable Resource Sub-System) Dynamics of Growth in a Finite World, by Dennis L. Meadows, William W. Behrens III, Donella H. Meadows, Roger F. Naill, Jørgen Randers, and Erich K.O. Zahn. 1974 (Especially Chapter 5: Nonrenewable Resource Sector) Economics models Resource economics Systems theory Simulation software