Total Quantity in Order

Is there a way I can add an area to the order details on the admin back in to say the total of the amount? Example:

4 - Extirpates

2 - Karpulsan Forest

3 - Blood Pet

Total Count: 9


Is this an easy thing to add? Our store deals with sometimes hundreds of items per order. It would be extremely helpful if we had an easy way to simply count how many items were in an order.