first of all, MBA degree is only one factor, a moderate one, not "God facotr", impacts on your career. The thought I can do everything (reasonable) I want after graduate from B-school is extremely wrong.
second, your past w/e plays an important role in your career development. people around 30 should at least be a section manager or a senior staff in the company (if not, let it be, enjoy your life). usally, these people dont want to be an entry-level employee again (no matter what happened). so, after graduate, back to where you come from could be a better idea. (specialized expertise, business knowledge, familiar ecosystem)
third, the ROI. I have to say it is a customized formula. not as simple as ROI = return / money I invested.
fourth, everyone should figure out one's own "gaming theory" in life. actually, there is no win-win scenario. just everyone get what he/she/it can want.
finally, you want to know some statistics, not advice. sorry, I cant share it with you. Its private information.
同意12楼的看法,尤其是第4点。如果有用ROI来衡量MBA,那是比永远都算不清的帐。“there is no win-win scenario. just everyone get what he/she/it can want”。如果不想一辈子都做本行,认为自己更适合management, finance,或者其他,那就换吧!转行肯定是有代价的,选择了一条路就走下去,不用回头看,只要做的是你想要的,开心就好。如果总是不时的比较收入代价,心态很难平衡的。