Inserting adding or creating a floating text box on Chart

I often want to add explanations or bits of text besides the Title, Axis Labels, Data labels and Legends that are provided in normal Chart formating options.

I've done this experimentally by trying to click on various areas of the chart and typing, and every once and a while a text box appears, deus ex machina, and once that happens, I select it and copy and paste to make others. But for the life of me I can't figure out how you are supposed to create a text box.

there doesn't seem to be a "text tool". There is nothing under the insert menu. I don't have any idea how I have done it, even when I manage to make one.

This is Excel 2004 on a Mac if that makes a difference.

Thanks,

Brian

I don't know about Excel 2004 but in 2003 you can display the drawing toolbar by right clicking an existing toolbar and then click the text box item and place it in your chart.