100% Stacked Column Chart
100% stacked column or bar chart is a good way to display some categories of a whole changing over time. For example, a company may use 100% stacked column chart to display what product lines contributed to its revenue by calendar quarter. The downside is that in such a chart it is quite difficult to visually compare the changes over time (except for the first item/series).
Key implementation details
You don’t need to perform percentage calculations in your code. You can pass your real values to amCharts and the chart will do the rest. For this purpose, we enable
calculateTotals (more info here) on the value axis (the Y-axis in this case) and set its range to 0 to 100 (plus enforce it with
strictMinMax to disable “smart” min/max features).
Then, in our series we set the
valueYField to our real value, as usual. But after that we take advantage of the “Display fields” feature in amCharts. Display fields allow us to reference derivative calculated values instead of raw values from our data set. In this case we want to set our respective display field (
valueYFieldShow) to display the percentage share of our real value. For this we set it to the
valueYTotalPercent calculated field.