Step 1: Determining the parts of the product systems for which forecasting is relevant        NO        YES Step 2: Determining the necessary detail of forecasting YES       NO     YES       NO        YES        NO Figure 6.1(a). Decision tree showing the 5-step procedure for forecasting product systems. Figure continues on next page. Are important developments expected? Conclusion can be based on general direction of development Conclusion can be based on relative speed of development Conclusion   can be based on general knowledge Forecasting not relevant Forecasting must include market situations and technologies at specific points in time Forecasting can be limited to the general direction and relative speed of development Forecasting can be limited to the general direction of development Forecasting must quantify efficiency and emissions of technologies at specific points in time Go to step 3