The outlet noted that the 14-time Grammy winner became a billionaire in October, due in part to an “estimated $190 million post-tax earnings from her historic Eras Tour.” Forbes also announced that Swift was “the first person to [become a billionaire] based solely on songwriting and performing.”

While Swift’s achievements are being celebrated, she has also faced criticism due to her private jet trips she’s taken due to the tour and her relationship with Kansas City Chiefs tight end Travis Kelce. Now a new study by Greenly has examined the singer’s carbon footprint.

Taylor Swift performs during “Taylor Swift | The Eras Tour” at the National Stadium on March 2, 2024, in Singapore. A new study has detailed the singer’s carbon footprint.ASHOK KUMAR/GETTY IMAGES FOR TAS RIGHTS MANAGEMENT

Newsweek emailed a spokesperson for Swift for comment Thursday.

Swift has two different private jets: the N621MM and the N898TS, which are Dassault’s Falcon7X and 900LX models respectively—one of which she uses to go to and from her concerts herself, and the other being used as a base in Nashville where her business is registered.

The study from Greenly focuses on her usage of the Falcon 900LX, her preferred private jet for long-distance travel. It is important to note that these calculations were made before Swift sold her Falcon900LX private jet in February 2024.

According to the study, during the American leg of her tour lasting nearly a year, Swift traveled nearly 37,053 miles, generating 77.5 tons of CO2e over almost 113 flight hours.

For her South American leg, the celebrated artist is believed to have emitted 61.6 tCO2e, having traveled 29,431 miles. Therefore, the Eras Tour has emitted 139 tons in CO2e emissions for 66,484 miles worth of travel for the North American and South American legs alone.

This does not consider the fact that Swift has also flown to Asia and Australia for her world tour and still has the European leg to go.

Swift was also estimated to have traveled 20,000 miles alone during the weekend of the Super Bowl to watch boyfriend Kelce play. She made two round trips across the Pacific Ocean for the Japan and Australian legs of the Eras Tour. These staggering numbers are likely to continue this summer as the tour arrives in Europe.

Much of the controversy over Swift’s private jet usage is due to what people deem as unnecessary travel. For instance, Swift was spotted traveling from Buenos Aires back to New York City in November 2023 before the Rio Shows began during the South American leg of the Eras Tour. Throughout the U.S. leg of the tour in Spring 2023, Swift often traveled back and forth between the city where she held her concert and her residence in New York City.

This isn’t the first time that Swift’s private jet usage has been of discussion.

Swift was previously named “biggest celebrity CO2 polluter” after the social media account Celebrity Jets trailed the private jet journeys of stars including Kylie Jenner, Stephen Spielberg and Drake.

Climate change advocates have also blasted Swift’s extensive use of her private jet on multiple occasions.

In February, celebrity jet tracker Jack Sweeney also shared information about the pop star’s private jet usage. According to Sweeney’s X account, formerly Twitter, Taylor Swift Jets (@SwiftJetNextDay), the 34-year-old’s private jet flights produced 77.8342 tons of carbon dioxide between December 25 and January 30.

The singer’s publicist previously told The Associated Press that “Taylor purchased more than double the carbon credits needed to offset all tour travel” before her tour began, but did not provide any further details.

Swift’s tour is set to conclude in December 2024. It’s seen unprecedented demand and has made over $1 billion—breaking the record for the highest-grossing tour of all time, according to Guinness World Records.

The tour’s last concert was a sold-out show at the 55,000-seat National Stadium in Singapore on March 9. She is taking an extended break before her next concert, which will be in Paris in May.