Undated -- With the super success of "Speak Now," we knew Taylor Swift was rich. Now Forbes tells us how much she made in the last 12 months. How does $45 million in one year sound? Forbes says that puts her on its new list of the 20 Best-Paid Celebrities Under 30. Taylor Swift is 21. Forbes says Miley Cyrus, who's 18, made $15 million in the last year. So did Carrie Underwood, who's 28. Lady Gaga tops the Forbes list with $90 million. Justin Bieber is the youngest on the list. He's 17 and earned $53 million from May of last year to May of this year.