The feature you are describing looks great but currently does not exist. That should probably be possible by using two reports results embedded in the same asp page, but I do not know enough about ASP to help you on that.
What you could do meanwhile is to create and run an Advanced SQL report that checks when a node has been down and for how long time.
A report that shows how long time a node has been down based on the events has already been posted by jtimes in the content sharing zone Outage Duration Last Month. I recommend you to have a look at it to pick up ideas.