In the Bar Chart, Histogram, and Timeline views, you can show data labels for bar segments and bar totals, as well as scale bars to 100%.

To create a 100% stack bar chart, go to the Axes tab in the Bar Chart Edit Panel and select 100% Stack Bars: 

Example of a 100% Stack Bar Chart

To add or change your data labels, select the Labels tab:

You can adjust which labels should be visible, the Node Label Source, Label size and density, and settings for the Data Labels.  Bar Data Labels can either be expressed in Values (a number) or Percentages, and can represent the node, or what the nodes are colored by.  Finally, you can choose to add Bar Totals.

In the Advanced settings, you can additionally adjust if the node label size is fixed or relative to the node, as well as the clustering and sub-clustering levels: