Please see the link in #34.
Exodus is working on their own statistical studies. I don't know when they'll be released.
"The surveys and studies are being done and information is being complied. I believe we will all see that the statistics for change are much higher than 30%. In the past 10 years First Stone Ministries has noted that the men and women who truly work through the program and wholeheartedly apply themselves reveal that the percentage rate of people who are able to overcome the homosexual lifestyle is much greater than 50%." 1999
That was 1999. Probably even higher today 2006 due to the knowledge "You have the choice to change IF you want to change" is no longer a secret.