When you hover over a party name inside of Tracts you see an overview of the interests for the party during that point in time. These interests are calculated from the amounts you’ve previously entered into the digital notecards. Each interest is represented by a letter (or multiple letters if the interests are the same amount) followed by the interest amount.
In this example, both the surface(S) and the entire bundle of sticks(M) is 1.25%.
When you’ve indicated breakout mode inside of a digital notecard. The interests present may look a little different. If S, E, B, D, I, or R is in front of M that means the letter is the only stick out of the bundle that is different.
Ex. B,I:0.02 M,S:0.0325
In this example, bonus and ingress are both 2% while the rest of the bundle of sticks (surface, executive, delay, and royalty) are all 3.25%.
You can find more information on what each abbreviation means here.