Is it possible to write an Excel VBA macro to add a chart to the sheet, or in a new sheet?

The problem is, when I call "Charts.Add" inside a function, it'll return None because we're not supposed to modify the workbook in an Excel Function right?

i.e.
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Now, I guess I can write a Macro, and then invoke it manually from Tools->Macro .. however, I can't pass any parameters through there...

So what are my options? I am trying to write a macro to create a chart using a passed in parameter as the data for the chart.