There is a change of style for the stacked area chart in QlikView from version 12.10 to 12.20. You can see the difference between the two versions if you have a dimension with positive and negative values.
The style of the stacked area chart (version 12.10 ) was adjusted as it had an arbitrary bottom when using negative and positive values for a dimension. That means that in this case the chart was filled starting from the bottom.
The chart in version in 12.20 has a zero-level as base approach, which means that when filling an area, it starts from "0" (the x-axis).
In the following example DIM1 has positive and negative values, DIM2 has only positive values.
You can reproduce it by uploading the following data:
LOAD * INLINE [
date1, DIM1, DIM2
01/04/2018, 76, 400
01/05/2018, -50, 500
01/06/2018, -20, 600
01/07/2018, -80, 800
01/08/2018, 190, 400
01/09/2018, 20, 300
01/10/2018, -40, 200
01/11/2018, -50, 400
In version 12.10 the chart looks like this:
In version 12.20 the area chart looks like this: