I don't think DreamHost publishes any figures on this. Some customers have posted figures from 3rd party website monitors, so a forum search should turn up some general figures.
Personally, my site up-times have been very good to excellent, except for a small period a few months ago when DreamHost were experiencing major network problems (now resolved). The small outages I do notice are usually over before I have time to lodge a support request.
That's good to hear.
In the future, it might be a good idea to post the actual DreamHost server you are on, so that others on the same server can let you know if they too are experience problems.
You can find the DreamHost server a particular domain is on by going to Users -> Manage Users in the panel and looking under the Machine column for the user that controls the domain.
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