Taylor Swift may have proven that writing about her ex-boyfriends is a formula which works, as she topped the Billboard Top 40 Money Makers list for 2014.

Taylor Swift's 2014 Grammy Performance [VIDEO]

The list, put out by Billboard Magazine, listed Swift as the top earning performer in 2013. The 23-year-old country star raked in just under $40 million, with her international RED Tour generating the most revenue. Her estimated $30 million in earnings from the tour alone also upped the ante for her sponsorships with Keds, Coke and Elizabeth Arden as she became what the magazine called "a mainstream go-to."

Also breaking into the top three were country superstar Kenny Chesney, and Justin Timberlake. The 33-year-old, who took a seven-year break from music released The 20/20 Experience, and went on two international tours, one with Jay Z. Combined, his tours earned him just over $30 million.

Beyoncé Will No Longer Use This Word.

Other top earners included Bon Jovi and The Rolling Stones, who each earned just under $30 million, while Beyonce placed number 6 with a reported $24 million in earnings. Her surprise self-titled album at the end of 2013 debuted at No.1 and sold 617,000 copies in her first week. Coupled with her earnings from The Mrs. Carter Show World Tour, she squeezed past her husband Jay Z, who made $15.6 million from his latest album, Magna Carta Holy Grail. Blue Ivy's dad also also had a great year for sales, with his album selling 528,000 copies in its first week with its own No.1 debut.

To see where other stars, including Bruno Mars, Justin Beiber, Maroon 5 and more placed, check out the full list here.

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