Include option to have 45° line in scatterplot

I noticed that there is no 45° line that can be optionally displayed in the scatterplot visual via "Add further analyses to your visual" button. I would need said line in cases where I would like to show that a given point is below, exactly on or above the 45° line. This is necessary in cases where I would like to demonstrate whether a customer with a share of 20% of sales is generating 40% of all profits and can therefore be considered to be disporportionally more imporatant towards the overall company profitability than their sales numbers would imply. A 45° line would help the reader of a scatterplot visual immensely in order to see which customers are disporportionally more important and which ones are less "performing".

Sure, I could manually insert a simple line here but I would have to constantly adjust it. Also, there would be more room for errors in case I would need to change the width-height ratio in from 1:1 to something else, thereby distoring the 45°-line so something that is not 45° anymore.