Before working with cost centers, you have to create at least one. Additionally to the normal keys of a dialog box you can close this box with . The -key (on the numeric-keyboard, too) has two different functions. At first, it works like the key. The "Entry" button will be framed simple. If you are in the text field, this button is framed double. Now the key executes the entry. The dialog box doesn't close after executing an entry. So you can enter many cost centers, one by one. You close the box by using the "Cancel" button. In this moment all values will be deleted.