Difference Node
This node is a final outout of a pivot analytic.
It selects a value that you want to use in your pivot.
A key distinction is that it's used when you want to measure the difference in a value between when the pivot began and when the pivot finished.
This is very useful if you're trying to capture how much of the value was transferred between A and B.
Additionally, if all of our output nodes are Difference nodes, the behaviour of the pivot analytic changes slightly - pivots where there was no change in value will be removed, as they're of no real use.
For more information, see Pivot Output Nodes.