Here’s a list of winners since 1968, the year in which the U.S. championships were opened to professionals:

2009 — Kim Clijsters

2008 — Serena Williams

2007 — Justine Henin

2006 — Maria Sharapova

2005 — Kim Clijsters

2004 — Svetlana Kuznetsova

2003 — Justine Henin-Hardenne

2002 — Serena Williams

2001 — Venus Williams

2000 — Venus Williams

1999 — Serena Williams

1998 — Lindsay Davenport

1997 — Martina Hingis

1996 — Steffi Graf

1995 — Steffi Graf

1994 — Arantxa Sanchez-Vicario

1993 — Steffi Graf

1992 — Monica Seles

1991 — Monica Seles

1990 — Gabriela Sabatini

1989 — Steffi Graf

1988 — Steffi Graf

1987 — Martina Navratilova

1986 — Martina Navratilova

1985 — Hana Mandlikova

1984 — Martina Navratilova

1983 — Martina Navratilova

1982 — Chris Evert Lloyd

1981 — Tracy Austin

1980 — Chris Evert Lloyd

1979 — Tracy Austin

1978 — Christine Marie Evert

1977 — Christine Marie Evert

1976 — Christine Marie Evert

1975 — Christine Marie Evert

1974 — Billie Jean King

1973 — Margaret Smith Court

1972 — Billie Jean King

1971 — Billie Jean King

1970 — Margaret Smith Court

1969 — Margaret Smith Court

1968 — Virginia Wade

Source: USOpen.org

How about $35 million a year in prize and endorsement money? That’s what Forbes estimates as Roger Federer’s total take over the past 12 months. While Federer may have relinquished his No. 1 ranking to rival Rafael Nadal over the summer, it’s still a blowout at the bank, where Federer outearns Nadal (an estimated $18 million) by nearly 2-1.

Here’s the Forbes list of the world’s wealthiest tennis players:

1. Roger Federer: $35 million

2. Maria Sharapova: $26 million

3. Rafael Nadal: $18 million

4. Andy Roddick: $15 million

5. Venus Williams: $15 million

6. Serena Williams: $15 million

7. Justin Henin: $10 million

8. Novak Djokovic: $9.5 million

9. Ana Ivanovic: $8 million

10. James Blake: $7.5 million

To read more about these players, and to see a slideshow, visit Forbes.com.