Terminal questions

So I have a terminal and I have allocated 20,000 to it and am using a little more than 19,000 with it for the flights that I have assigned for that terminal. But I noticed today that there is a "used" column that says only 9861. What does this mean exactly? I have attached a screen shot for what I am talking about 

That means that in the current week (since your last week end closing) you have used 9861 of the 19000 assigned.