You've already answered your own question-since they are losses (and shouldn't be added to the whole) should be removed from the columns. You can do this in one of two ways: either zero them out (which wouldn't allow you to evaluate them in terms of the whole) or assign them a negative value. By assigning a negative value, you can still compare the relative magnitude of loss compared to the whole.
The problem is that your Y-axis begins at 3400. This is causing you two issues. First, it makes the loss "disappear" when you converted it to a negative number. In actuality, it was there just outside of the range of your chart.
Also, there is a significant problem with cutting the base of of your columns. Column charts should always begin at 0 (due to the ability to judge the columns length in relation to the others). By truncating the columns, you over-emphasize the relative impact of the smaller values. For example in your "2 Months" column, the "Extended" values appear to be almost as great as the "Active", when in fact they're really only about 10% of them.
Here is an example of the full height columns with losses scored as a negative value. They're inverted (below the 0 Y-axis), but you can still judge their relative magnitude in relation to the wholes. The result is the values are very small, but they should be-they only represent about 1-2% of the whole.