Scatter Plot how to make dot bigger if multiple values

I am plotting some x values against y values. Have quite a lot of data. Some of this is the same value for both x and y (eg mutiple versions of the same x,y combination) . however, when i make the scatter chart/graph the dot that represents this is the same size as when there is only one set of the x,y value.
I want the graphic/chart to show that there is more than one of this combination hence you can visually see which x,y has the most repeats.

Any easy way of turning this on in excel?

thanks in advance

Stuart

Thanks Andy.

Never used that before, do you know of a helpful guide or link?