The value is available after the first set of -how ever many you have set- captures as 'dist' on the Analyze tab where you can see when an align has been triggered. The value is also available on the Capture tab. If the drift is greater than that set, the alignment can also be followed -as per any align instance- in the message box at the base of the Align tab.
Analyze does show those numbers, at least for me.
See the screenshot below
If you click on a capture, the number to the right of "dist" should show you the target distance for that capture (15" in the screenshot), and if you have the checkbox to the left of dist checked, then the plot will appear. If you have "latest" clicked near the top, the the stats and graph should be continuously updated as the night progresses.