The Venn visualization lets you drag in up to 3 segments (from Components) and one metric to build a Venn diagram.
You can then hover over the segments to gain more insight into percentages, etc.
To turn the Venn diagram into a Freeform table, click the colored dot next to the Venn header and select Manage Data Sources > Available Data Sources > Freeform Table.
To normalize the Venn diagram (take the size out of it), go to its Visualization Settings icon and select Normalization.
Here is a video on the Venn diagram: