Hi, for the y-axis, should we always start with 0 or can we set an appropriate scale? For example, if the two values on y-axis are 105% and 95%, can we set the scale from 90% to 110% to make the comparison more obvious?
You should pick suitable values for the axis ranges that allow the message you're trying to convey in the graph to be clearly expressed. If you're trying to say 'The values in the scenarios are all reasonably similar, with minor changes between them', then giving the y-axis a range from 0 to 110 would make that message clearer. If you're trying to say 'The values change notably from scenario to scenario' then making the range narrower would increase the appearance of volatility. You decide what message you want to give, and adjust the graph accordingly. The message of the graph should tie in with what you're saying about the results elsewhere. Remember that this exam is much more about communication than anything else. What results are you getting? What do they mean? What should your boss do about them? These are the questions that you should be asking, and the answer to those should make it more obvious what the graph should look like.
