Defined distribution of traffic in the View field can be further analyzed by picking the preferred traffic direction. Offered traffic direction is the result of the selection you have made in the View field.
For example, if you want to monitor which conversations are consuming the most of your traffic, you can do that by observing Total distribution of traffic between Source (Src) and Destination (Dst) or by observing the aforementioned traffic distribution by opting for conversations between Initiators and Responders (Ini/Res).
In the chart title, options are characterized by plus or minus symbol, an indication of positive or negative traffic movements respectively.
To learn more about Options field read Traffic Views.