creating a chart for tracking history prices

[happydz]

Hi
I need to create a chart using excel to track the supplier history prices. To make it easier for you to understand my thread, I'll give an example:
let's say the supplier set a prices for a specific product as following:


Nov 07, 2017 $30
Nov 15,2017 $20
Dec 20,2017 $29

Now, the idea is that I want to enter the new price in the cell without losing the previous price so that in the end of every month I will be able to make a chart of history changes of the prices of the specific product.

I appreciate any help from you

thank you