I hear mixed opinions on this. Some say if you are calculating the change in profits (say revenues increased 20% and costs decreased 10%), it is better to calculate on an incremental basis (I.e find 20% revenues and then add 10% costs to get change in profits). But others say this might be hard to follow for a client and you may lose points for not being client friendly, so it's better to calculate old profit , then new profit and subtract the two to get the difference. That's easier to understand and follow when you communicate it. The example used here is simple but there may be calculations where there are multiple cost and revenue components that are changing. So is it better in general to avoid the incremental basis calculation (to avoid mistakes and be client friendly)
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