Graph that displays changes made to itself

It will all depend on how you intend to interact with the spreadsheet and the chart and the data and such. I think we will need to understand somewhat how you interact with this file, how data starts, how data is changed, etc.

Spreadsheet charts are designed to chart data that is stored in the spreadsheet. They can't simply "remember" what was there before something changed. Here's what I would expect to do for something like this:

1) I have the data I want charted in the spreadsheet. Create the chart.
2) When something changes, make a copy of the old data. Make any changes in this new copy of the data.
3) Add this new data to the chart as a new data series.
4) Repeat steps 2 and 3 whenever a change is made.

Can you interact with the spreadsheet in that way?