It is possible to view the results of a survey by events individually, although the information is not summarized the way it is in the Survey Report.

All you need to do is run the Participants Report (Detailed) (making sure to include the survey information by checking the box before exporting to excel). From there you can see what each participant entered for their survey results. With a little Excel knowledge, you could even sort, separate, and then summarize that information by event or participant (or any other field in the Event report, shirt size for example).