Real Madrid have retained their place as the most valuable football team in the world for a third straight year, according to Forbes.

The reigning European champions' value has dropped five percent to $3.26 billion (£2.13 billion) this year, but their $746 million (£489 million) revenue is the highest of any sports team in the world.

Rivals Barcelona are second in the 2015 list with a value of $3.16 billion (£2.07 billion) after a one percent drop, followed by Manchester United at $3.10 billion (£2.03 billion), who, unlike Real and Barca, recorded 10 percent increase in value from last year. Bayern Munich are fourth at $2.35 billion after a whopping 27 percent increase in value.

In addition to Real's record take-in, Forbes estimates revenue for 2013-14 was $657 million (£431 million) for Barcelona, $703 million (£461 million) for United and $661 million (£434 million) for Bayern Munich.

Value is estimated using April 22 exchange rates and revenue with average rates for the 2013-14 season.

Forbes' top 10 most valuable teams of 2015:

1) Real Madrid $3.26 billion (£2.13 billion)

2) Barcelona 3.16 billion (£2.07 billion)

3) Manchester United $3.10 billion (£2.03 billion)

4) Bayern Munich $2.35 billion (£1.54 billion)

5) Manchester City $1.38 billion (£905 million)

6) Chelsea $1.37 billion (£898 million)

7) Arsenal $1.31 billion (£859 million)

8) Liverpool $982 million (£644 million)

9) Juventus $837 million (£549 million)

10) AC Milan $775 million (£508 million)

Premier League teams accounted for eight of the top 20, with Tottenham ranked 13th, Newcastle 18th and West Ham 19th.

Information from The Associated Press and Press Association was used in this report.