Up to now, tables did not work very well on our new site because they were not responsive, eg, they looked AWFUL on a mobile device. Now, you can now insert tables and they will resize beautifully on smaller screens. Tables must be used for data only, not to design or lay out your page.
Did you read that? Tables are for data only!! This is a change from our last site. It's very important, because if you use a table for design, the mobile version will be completely messed up.
For example, here is the table at full width:
And the same table displayed on a mobile device:
To insert a table, use the new buttons in the editor. You should (probably) set the first row to be a header: