This is the wrong place to be asking this question, Off the stack is the place. As mentioned though I suspect testing centres keep that information confidential. There are probabnly many factors that influence this stat i.e. age, location, course level, language course is presented in and if if english is english the persons first language. Thats also not including if the person is competant to take the course.
At the end of the day training providers make their money whether the users pass or fail.
@MeredithW can this be moved pretty please!