at 65 minutes per player. As 30-minute to 65-minute-per-player time controls are also under the Regular rating system, these games affect both the Quick and Regular ratings and are known as dual-rated games. However, the K factor (a statistic used for ratings) is reduced by comparison, meaning that players will either lose or gain (or rarely both) fewer rating points compared to a solely Quick or Regular game. Any time control over 65 minutes counts under the Regular rating only. All of these time controls include the delay added to the time control, such as a 60-minute game with a 5-second delay, which is still considered to be a 60-minute game, not a 65-minute game. As of March 2013, the USCF has also added a separate Blitz class rating for any time control between 5 and 10 minutes per player. It is not possible for a game to be dual rated as both Blitz and Quick. Unlike Quick chess, 5 minutes can also mean game 3+2 (three minutes with a two-second increment). World championships Both official and unofficial FIDE-sponsored world championships for fast chess have been held since the 1970s. World Rapid championships before 2012 In 1987, Garry Kasparov (the World Champion of classical chess at the time) and Nigel Short played a 6-game exhibition Rapid match ("Speed Chess Challenge") at the London Hippodrome, won by Kasparov 4–2. The 1988 victory by Anatoly Karpov in Mazatlan was officially called the World Active Championship, but FIDE changed the word 'active' to 'rapid' soon after. In 1992, FIDE held the Women's World Rapid and Blitz Championship in Budapest, Hungary. Both Rapid and Blitz Championships were won by Susan Polgar. The 2001 victory by Garry Kasparov in the FIDE World Cup of Rapid Chess (organized by the French Chess Federation in Cannes) was held contemporaneously to the Melody Amber rapids (thus splitting the top players between the two events), and it is sometimes considered to be official, although it was never named as a "championship" but rather a "world cup". Viswanathan Anand won the official FIDE 2003 Rapid Championship at the 6th Cap d'Agde event. After no bids in 2004, FIDE optioned the 2005 Rapid to Cap d'Agde, but it was not held. Teimour Radjabov won the 2006 7th Cap d’Agde Rapid Chess Tournament, but this had no FIDE status. The yearly Frankfurt or Mainz events hosted by the Chess Tigers (2001–2010) were