Thank you for your post. There is currently not a report that shows the elapsed total time for a patch deployment that was run. With the reports that we currently have available, you can run those and then estimate the time based on when you see the first patch started and when the last patch finished.
The report that you're looking for would require a feature request to see if we can have that added to a future update of Ivanti Patch for Windows. That request can be submitted here and any updates that come in on that feature request would notify you.