"Billboard" has released their annual "Music Moneymakers" list, which ranks the Top 40 artists who raked in the most income during the previous year.

The final estimates are drawn by compiling data from:  album sales, digital music sales, online music and video streams, and revenue from touring... which is where the big money comes from these days.

"Billboard" did make one change to the list this year.

Since they only count U.S. music sales, they decided to only count DOMESTIC touring.  So bands that spent a lot of last year touring abroad... like U2, AC/DC and METALLICA... took a hit in this year's ranking.

Also, income from merchandise sales, sponsorships, DVDs, ringtones, and songwriter royalties from radio wasn't included, because there isn't enough data available to make it consistent across the board.

In the end, LADY GAGA was #1, with an estimated net income of $30.6 million last year.  BON JOVI was a close second with $30.4 million.

Here are the Top 20 Music Moneymakers:

1.)  Lady Gaga... $30.6 million

2.)  Bon Jovi... $30.4 million

3.)  Roger Waters... $24.5 million

4.)  Dave Matthews Band... $23.9 million

5.)  Justin Bieber... $22.5 million

6.)  Taylor Swift... $20.7 million

7.)  Michael Bublé... $19.8 million

8.)  Eagles... $18.3 million

9.)  Black Eyed Peas... $16.8 million

10.)  Paul McCartney... $14.2 million

11.)  Tom Petty & the Heartbreakers... $14 million

12.)  Brad Paisley... $14 million

13.)  Carrie Underwood... $13.5 million

14.)  Tim McGraw... $13.5 million

15.)  Usher . . . $13.2 million

16.)  Rascal Flatts... $12 million

17.)  Jay-Z... $11.6 million

18.)  Eminem... $11.2 million

19.)  Phish... $10.5 million

20.)  Eric Clapton... $10.2 million

The list also includes:  Carole King and James Taylor, #25 and #26… the "Glee" cast, #28... Susan Boyle, #36... and Michael Jackson, #37.

The only acts in the Top 40 who DIDN'T do any real U.S. touring last year were:  Eminem, Susan Boyle and Michael Jackson, of course.

(For the complete list... including the estimated incomes down to the DOLLAR, and "Billboard's" mini write-ups on each one, hit up this link.)