Excel - Correlation of data points

[frobledoc]

This may be very simple, but I am not an Excel expert.

I have a series of data: on one hand, I have 15 years (2005, 2006,....,2019), and on the other hand I have my total sales each year. I would like to calculate the average percentage at which my sales have grown over these 15 years with respect to my first year.

Your help will be appreciated.

[#2]

In fact, yes, it should be pretty simple, but we can offer specific help if you would be so kind as to upload a sample of the data....just make sure there's no proprietary info in it. Part of the answer would be dependent on how you have the information arrayed on your spreadsheet(s)