Tiger Woods' estimated endorsements for 2010 are worth 31 million dollars less than in 2009.
In Sports Illustrated's yearly analysis of the top-earning US sports figures, Woods is still number one on the list, as he has been for the rankings' seven years.
But his estimated total earnings of more than 126 million are down 30 per cent from nearly 180 million two years ago.
Golfer Phil Mickelson is again second with total earnings of more than 85 million dollars.
Swiss tennis star Roger Federer topped the separate list of international sports figures, dethroning English footballer David Beckham with nearly 86 million dollars total earnings by Sports Illustrated's reckoning.
Beckham fell to number three on the list, behind Argentinian footballer and reigning FIFA World Player of the Year Lionel Messi.
On the US list, boxer Floyd Mayweather jnr was third, followed by NBA star LeBron James and baseball player Alex Rodriguez.