Your Stats Overview is just a basic snapshot of the overall metrics and performance of this marketing plan.  If you click on the STATS ICON on the top right corner of your planning canvas it will bring up your Stats Overview.

Here you can see your overall Unique Visitor flow, how many Leads you've gotten, your Total Sales (Product Sales, Upsells, Downsells), your Average Visitor Value, Average Lead Value, Average Transaction Value (2 Product Sales + 1 Upsell + 1 Downsell purchase to the same Unique Buyer = 1 Transaction), Total Expenses and your Overall Total Revenue.  This is a great tool to see in one click how your overall marketing efforts are performing!  To see more specific data with information funneled down to your specific Ad Sets you will want to review the Stats Table section in Live Analytics.