General Motors India, makers of Chevrolet Aveo and compact car Spark, reported a 64% increase in sales during September this year.The company sold a total of 5,751 in the month, as against 3,506 units during the same month last year.Commenting on the performance, P Balendran, VP, GM India, said: "The year 2007 so far has been a remarkable and wonderful period with all the recently launched cars receiving rave reviews from the market and growing acceptance from customers."Sales figures for the half yearly period from April-September stood at 30,823 units up 60%from the same period last year.