The use of “sensitivity analysis as a thought-process” (in model design) does not involve producing any numerical results, since the model is not yet built. When a model is either built (or is being built), the simplest way to create numerical sensitivity analysis results is to do so manually. That is, one simply changes the value of an input variable and observes the effect on the output(s). (Of course, whilst this is simple to do, it may not always be the most efficient way, for reasons discussed later).
There are two variations of how to run this manual analysis:
For the following exercise, please work with a copy of the model that you built previously (in the Starter course). For reference, this initially should resemble the items and calculations in the following image (excluding column E, which you do not need to build, at is shows the formulas used in column C, and is provided for additional reference and clarity):
Then (referring to the image below for the completed results):
In general, this manual approach to sensitivity analysis gives valid results, it is not recommended as a standard approach: The resulting numbers are not linked to the model, and will not update if the values of other model inputs are altered or if other changes made to the model. Thus, the recorded values are likely to become outdated and make be used in an incorrect way in subsequent analysis or presentation of results. Most often, the better approach is to automate the processing using a DataTable, as discussed in the next sections of this Chapter.