The 1991 IndyCar season, the thirteenth in the CART era of U.S. open-wheel racing, consisted of 18 races, beginning in Surfers Paradise, Queensland, Australia on March 17 and concluding in Monterey, California on October 20. There was one non-championship event, the Marlboro Challenge. The PPG Indy Car World Series Drivers' Champion was Michael Andretti, the Indianapolis 500 & Marlboro 500 winner was Rick Mears. Rookie of the Year was Jeff Andretti. The 75th Indianapolis 500 was sanctioned by the USAC, but counted in the CART points standings. Taken from http://en.wikipedia.org/wiki/1991_IndyCar_season.