KB0077: How do I mix positive and negative values in a waterfall chart?

Explanation

In think-cell's waterfall chart, you can have stacks (columns) consisting of multiple series. However, the total of a stack is always the total of the absolute values within the stack. The total on top of the stack labels the extent of the stack, not the sum of its (negative or positive) components. This is not an error.

By design, waterfall charts are not suitable for displaying positive and negative numbers within the same stack. All numbers within a stack should be either positive or negative. A stack containing a mixture of positive and negative values cannot be displayed appropriately. For example, where should the connector on the side of the stack connect to the next stack? Top, bottom, somewhere in between? Keep in mind, that each connector not only connects two stacks, but at the same time is also a water level mark which — when projected to the value axis — has some meaning of its own (the total of all waterfall stacks so far).

Only extents count in the waterfall chart, and negative values have the same extent as positive values (it is not possible to "show a negative extend"). Therefore, if you have positive and negative numbers within the same waterfall chart, and you want to use this particular chart type, you cannot have them within the same stack. Just put them into separate stacks next to each other.

See also

KB0078: Totalling multiple series in parallel in a waterfall chart