Chart showing rates of increase

[Guest]

I am a trainer and have been given the fictitious scenario described below
to test my Excel skills.

My question is: What is the best way to build a chart to show the RATES OF
INCREASE between Price of Crude Oil and the Cost of Heating Oil for three
different companies. Here is he scenario:

You are asked to put some learning together for a group of litigation
attorneys who will be off site for a trial. They need to learn the easiest
way to turn an excel spreadsheet into a chart and put it into PowerPoint
presentation.
The spreadsheets are not very complex they say. They are tracking the
increase in cost of heating oil for three different companies over a five
month period against the cost of crude oil. The case is a lawsuit about how
heating costs are rising at a much higher rate than the price of crude oil.

I'm guessing a chart with lines--one showing the cost of crude oil over the
five months and then three other lines showing the costs of heating oil for
each of the three companies. Is there some way to show not only the
DIFFERENCE in costs, but also the RATE OF CHANGE of the difference in costs?

THanks for any help you can give-- Kevin

 

[Bernard Liengme]

The rate of change is
(measure at time t2 - measure at time t1) / (t2 - t1)
This gives the slope of the line when measure is plotted against time
Without seeing the data I cannot be of more help
best wishes