Go to "Inventory" using the tab on the left hand side.
Hover over one of the column descriptors and then click the three dots which appear. Select "Manage Columns."
For ROI: Turn on the tab for "ROI."
For Revenue: Turn on the tab for "Revenue."
Scroll to the bottom of the page and in the bottom right hand corner make sure that all of the rows are visible on the page.
In the bottom left hand corner select "Export."
See below for a visual representation of adding the ROI column.