Here is a post about the UCSC appeals:
https://www.reddit.com/r/ApplyingToCollege/comments/868g5y/uc_santa_cruz_waitlist_appeal_letter/
http://talk.qa.collegeconfidential.com/t/ucsc-appeal/
What is your basis for an appeal? Do you have documentation that proves your statement(s)?
I do not have any appeal stats to post for you but know they are rarely granted.
Best of luck.