You basically just get the YouTube earnings mentioned when to the "total estimated earnings" area to the right. You don't need to add or minus anything from it. This amount is actually the amount from the 60/40 split between you and YouTube. The full amount of money gained by your ads BEFORE the split is shown in the ad performance area underneath the estimated earnings link to the left.
Also you will not gain any money until you earn $100 in your estimated earnings NOT your ad performance. If the amount you have it below the payment threshold of $100, the money you have earned that month will carry to the next month (payments are issued on a monthly basis).