On the main screen directly under Publishers (or Placements if you’re in that level), there’s an option for Show/Hide Graph.
Clicking on this will expand (or hide) a new chart that shows all of your stats at a glance.
The boxes above can be customized to show only the stats you care about by clicking on the arrow on the far right of each column.
The graph below is a two axis line chart that plots two different stats over a custom time range. The y-axes can be edited to show the relationship between different stats like spend vs. revenue, impressions vs. clicks, or click-through-rate vs. conversions.