Revenue/Expenses lumped together on P&L for specific revenue types

I'd like to be able to set up revenue accounts so that the expenses directly associated with those revenues were netted together on the P&L. I'd just like to view the P&L with the revenue and expenses directly underneat it, with a net total of the two.

For instance:

Annual Dinner Revenue 4000

Annual Dinner Expenses 3000

Net Revenue Annual Dinner 1000

Does anyone know how to do this?