Madonna tops Forbes' list of highest-earning celebrities

Nothing seems able to stop the Material Girl from acquiring even more material, as singer and performer Madonna ranked at the top of Forbes' annual list of top-earning celebrities.

Forbes estimates that between June 2012 and June 2013, Madonna made $125 million US, mainly bolstered by a tour to accompany the launch of her newest album, MDNA.

The tour visited 67 cities for 88 performances, raking in more than $300 millionand making it the highest-grossing concert tour of 2012.

"Madonnas success, at age 55, just goes to show the incredible power of a successful music career," said Forbes, adding that the Queen of Popmade more in the last year than any single year since the magazine began compiling its Celebrity 100 lists in 1999.

Forbes estimated celebrities' earnings by speaking to agents, managers, producers "and other in-the-know folks" to compile the list.

Spielberg, Stern and Simon also rank

Film director Steven Spielberg ranked second with $100 million. Royalties from DVD sales and Universal theme park ticket sales earn him millions with his extensive back library alone. Forbes reports that last year's critical hit Lincoln earned $275 million on a budget of $65 million.

Television producer Simon Cowell, 50 Shades of Grey author E.L. James and radio personality Howard Stern tied for third with $95 million each.

Singer Lady Gaga, who has been compared with Madonna in the past, earned $80 million, placing her in the Top 10. But Gaga ranked first in Forbes' Celebrity 100 Power list, followed by Beyonc at second and Madonna at third.

Oprah Winfrey topped the overall Celebrity 100, which combines fame, money and power into what one might consider the ultimate measure of success in the spotlight.