1973: Virginia Slims Championships in Boca Raton; Evert won again in an expanded 32-players field; No.2 seed Court didn't even make it as far as the first round this time, withdrawing before her first match due to injury.

1974: Virginia Slims Championships moved indoors to Los Angeles Arena; 16-players, knock-out draw; Evonne Goolagong ended Evert's two-year reign (and 12-match win streak at the event) to claim $32,000 first prize from total purse of $150,000.

1975: Tournament switched dates from October to April; Evert won her third Virginia Slims Championships title and $40,000 for defeating Martina Navratilova 6 - 4, 6 - 2.

1976: Round robin format - two groups of four players, after first round elimination; Goolagong outlasted Evert in three sets at the LA Coliseum Arena, 6 - 3, 5 - 7, 6 - 3.

1977: Championships moved to Madison Square Garden, New York City for first time; 16-player field reduced to Round robin; Evert reached her sixth successive Championships final, defeating Brit Sue Barker for her fourth title.

1978: Moved to Oakland Coliseum, California; Navratilova won her first Championships crown, defeating Goolagong-Cawley for the $50,000 first prize.

1979: Avon (Cosmetics) took over sponsorship of the January-March Indoor Winter Circuit; $300,000 Avon Championships returned to the Garden (and would stay there until 2000); Navratilova downed 16-years-old Tracy Austin in three sets for $100,000 top prize in the eight-player double-elimination format draw.

1980: US Open champion Austin gained revenge, toppling Navratilova in three sets, a victory which catapulted the teenager to the top of the Tour's computer world rankings.

1981: Avon Championships saw the oldest player, 24-years-old Martina Navratilova, defeat the youngest competitor (and record youngest finalist at 15 years, nine months, 25 days), Andrea Jaeger, 6 - 3 7 - 6(3) for only the second time in five meetings.

1982: In the absence of Evert, Austin and Jaeger, unseeded Sylvia Hanika became the first German winner by stunning top seed Navratilova, halting the world No.1's 1982 unbeaten run at 27 matches.

1983: Virginia Slims returned as world title sponsor of the first unified circuit in women's tennis; Top 16 singles players and Top 8 doubles teams, based on the Championships Points System, assembled in the Garden for the $350,000 knock-out tournament; after defeating arch-rival Evert 62 60 for her fourth title and $80,000 winners cheque, Navratilova claimed she was "playing on another level now."

1984: Slims purse raised to $500,000; Navratilova triumphed over Evert again, this time 63 75 61, in the first best-of-five-set women's match for 83 years; Martina won $125,000, a record first prize for a women's only tournament.

1985: Navratilova avenged 1984 Australian Open semifinal defeat to Helena Sukova 63 75 64.

1986: (March) Navratilova avenged 1985 US Open final loss to Hana Mandlikova by winning first four-set Championships final, 6 - 2, 6 - 0, 3 - 6, 6 - 1.

1986: Due to end-of-season date change, a second Virginia Slims Championships was held during third week of November; Navratilova won a record fifth consecutive Championships title (and eighth in all) by dealing 17-years-old Steffi Graf a 7 - 6(6), 6 - 3, 6 - 2 loss in the title match; 30-years-old Navratilova, who became the oldest Virginia Slims Champion in the prestigious event's history, said after her record eighth win, that the Championships "is a showcase for women's tennis."

1987: Championships purse doubles to a record amount for a women's tennis tournament, at US$1,000,000; Navratilova suffers her first loss at the event since the 1982 final, going down 6475 to 17-year-old Gabriela Sabatini in the quarterfinals, halting a sequence of 21 matches without defeat, also ending 10 straight final appearances dating back to 1978; world No.1 and Roland Garros champion Graf takes her first Virginia Slims Championships and $125,000, stopping Sabatini in four sets, 4 - 6, 6 - 4, 6 - 0, 6 - 4.

1988: Pam Shriver upsets both Evert and Graf en route to her most important singles final since the 1978 US Open, falling to Sabatini in three sets.

1989: Graf takes her second Slims Championships title with a four-set victory over Navratilova, tying their head-to-head series at seven wins apiece.

1990: Kraft General Foods steps in as world Tour sponsor, but Virginia Slims retains control of the end-of-season Championships; total purse increases to $3,000,000; 16-year-old Monica Seles becomes the youngest Championships winner in history, by outlasting US Open champion Sabatini 6 - 4, 5 - 7, 3 - 6, 6 - 4, 6 - 2 in three hours, 47 minutes, the first women's match to extend to five sets in 89 years; champion's prize money increases to $250,000.

1991: In a repeat of the US Open final, Seles defeats Navratilova (playing her 13th Championships final), in four sets; Navratilova and Shriver, arguably the greatest women's doubles team of all time, make it a perfect 10 out of 10 in Championships finals; it is the last of 12 Championships doubles titles for Navratilova, having also won in 1977 (with Betty Stove) and 1980 (with King).

1992: Seles repeats over Navratilova, this time in three straight sets, to become only the second woman behind Navratilova (1983 - 85) to claim a hat-trick of Championships titles.

1993: Graf won her third crown, defeating Arantxa Sánchez-Vicario in a four-set final.

1994: Tournament sponsored by Virginia Slims for the 20th and last time, despite offering a record $3,708,000 (including Bonus Pool money) for a women's only event; after qualifying a record 22 times (1974-94, missing only 1990 due to injury), and taking a record eight singles titles from 14 finals, Navratilova's singles career ends in the opening round, falling to eventual champion Sabatini 6 - 4, 6 - 2; in an upset-strewn event (for the first time, the Top 2 seeds fell before the semifinals), unseeded Sabatini ends a 42-tournament drought by defeating 18-year-old Lindsay Davenport in three straight sets.

1995: Corel Corporation debuts as world Tour title sponsor at the 1995 $2,000,000 WTA Tour Championships; Graf defeats unseeded compatriot Anke Huber (third unseeded finalist) 61 26 61 46 63 for her fourth title and $500,000 first prize.

1996: Chase Manhattan Bank steps in as tournament title sponsor; in her 12th Championships appearance, Graf finally defends her crown, defeating rising star, 16-years-old Martina Hingis 6 - 3, 4 - 6, 6 - 0, 4 - 6, 6 - 0 in the third Championships five-set match.

1997: In the 25th anniversary of the Championships; Jana Novotna finally broke through to win her first big singles title over Mary Pierce, the conqueror of top seed Martina Hingis in a dramatic three-set quarterfinal; Novotna's straight-set victory over Pierce took the Czech back to No.2 in the world to conclude her best season to date.

1998: After a 10-tournament barren stretch which saw her relinquish her No.1 ranking to Davenport, No.2 Hingis comes back to win the Championships (at 18 years, 2 months, the fourth youngest winner after Seles, Austin and Evert), defeating arch rival Davenport in four sets, the last time the final would be played as a best-of-five set match; Graf, a last minute qualifier by virtue of her tournament wins in Leipzig and Philadelphia, goes on to upset Novotna and Seles in two thrilling matches before Davenport and a hamstring injury ended her run in a three-set semifinal.

1999: The Championships reverts back to best-of-three-set final for first time since 1983; in a repeat of the 1998 final, Davenport asserts her dominance over Hingis, winning in straight sets.

2000: Sanex bodycare products become the Tour's title sponsor while it's the Madison Square Garden swansong; in the absence of both Williams sisters, Venus and Serena, Hingis wins her second Championships title over former three-time winner Seles in a dramatic three-set final; Seles leads 7 - 6, 4 - 2 but can't prevent Hingis from claiming her ninth title of the year; Seles was appearing in the final for first time since winning the last of her three titles in 1992.

2001: Event moved to Olympiahalle, Munich after 22 straight years in Madison Square Garden; prize money purse increased to $3,000,000 and $750,000 for the winner; Serena Williams became the first player making her debut in the event (after injury forced her out in 1999 and 2000) to win the title when Davenport had to forego the final due to a right knee injury sustained on the penultimate point of her dramatic SF vs Kim Clijsters.

2002: The season-ending Home Depot Championships presented by Porsche are held for the first of four times at STAPLES Center in Los Angeles; in a major upset, Serena Williams, the undisputed No.1 and winner of three Grand Slam singles titles in 2002, is beaten in the final by Clijsters, who claims her first Championships crown with a 7 - 5, 6 - 3 victory

2003: The Bank of America WTA Tour Championships presented by Porsche return to a round robin format for the singles event, with eight players placed into two pools to produce four semifinalists; Clijsters is the only player to win all three of her pool matches and maintains the momentum to beat Capriati in a three-set semifinal and Mauresmo 6 - 2, 6 - 0 in the final; Clijsters earns $1 million as singles champion, the largest ever winner's purse at a women's only sporting event.

2004: Capping a breakthrough season which earlier saw her claim the Wimbledon title, 17-year-old Maria Sharapova becomes the first Russian to win the Championships singles title and only the second to win on debut, defeating Serena Williams 6 - 2, 6 - 4 in the final, having trailed 4-0 in the final set as Williams battled an abdominal injury.

2005: Sony Ericsson comes on board as global title sponsor; in the last of four stagings at STAPLES Center, it's a first-ever all-French final and Mauresmo becomes the first all-French champion, defeating Mary Pierce in a dramatic three-set decider; Lisa Raymond and Samantha Stosur take the doubles title over Cara Black and Rennae Stubbs, having trailed a set and 5 - 2.

2006: The Sony Ericsson Championships was staged for the first time in Madrid, Spain. Belgian Justine Henin secured victory having never previously advanced past the semifinals and having missed the previous two editions due to injury. The victory also helped Henin finish the season ranked No.1 on the Sony Ericsson WTA Tour. Lisa Raymond an the doubles title over Cara Black and Rennae Stubbs.

2007: The Sony Ericsson Championships returned to Madrid, Spain for the second year in succession and Belgium's Justine Henin retained her title at the prestigious season-ending tournament, with an epic three-set final victory against a rejuvenated Maria Sharapova. The victory also helped Henin consolodate her position as the No.1-ranked player on the Sony Ericsson WTA Tour. Cara Black and Liezel Huber took home the doubles title with an enthralling final victory over Katarina Srebotnik and Ai Sugiyama. It was the last year the Sony Ericsson Championships would be held in the Spanish capital, with the event moving to Doha, Qatar 2008 to 2010 and to Istanbul, Turkey from 2011 to 2013.

2008: The Qatari capital of Doha staged its first-ever Sony Ericsson Championships, the first time the Tour's year-end event was staged in the Middle East. With $4.55 million in total prize money, Venus Williams defeated Vera Zvonareva in a three-set singles final to win her first Tour Championships title, while Cara Black and Liezel Huber successfully defended their doubles crown. During the event, Tour pioneer Billie Jean King was announced as a Global Mentor for Gender Equality as part of the Sony Ericsson WTA Tour's partnership with UNESCO.

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