I have a worksheet with a2-ak as the month, a3-a10 as the practice and b3-k10
as the data. I saw on a website a way that if you move the mouse over to the
titles of the month or practice and click on them a graph will appear
depending on where you click. (The months were coloured orange and the
practice coloured blue.) You just click outside of the data to make it
disappear. How do I set up my worksheet to do this?

example
Jan Feb Mar Apr
BSI 1 5 10 2
CEI 3 20 2 5