Automatically charge tax on shipping

Automatically charge tax on shipping

When we do a quote we charge tax on the subtotal cost, but when I put in shipping I have to manually select a tax amount. 

How do I have it automatically apply tax to the shipping as well?

I have provided a screenshot that shows I have to manually do this. Seems odd its not an option as our sales staff keep forgetting to do it and it's costing us money.  Surely I'm missing something.

    Nederlandse Hulpbronnen