The Rating displayed is the Average of all the ratings received by the Entry.
Average of Star Rating is calculated as (Sum of all the ratings given by the users) / (Number of users who gave the ratings).
For example if 5 users have given ratings for an entry as given below -
User 1 - rated 5
User 2 - viewed the entry but did not vote
User 3 - rated 4
User 4 - rated 3
User 5 - viewed the entry but did not vote
Then Average Rating would be (5+4+3)/3 = 4. This is the value that is displayed against that entry in the report that is downloaded.