Car sales in the country rose 12.9 per cent, year-on-year, to 1.73 lakh units in December, amid heavy discounts by manufacturers. Car sales have now increased for the 14th straight month. According to data released by the Society of Indian Automobile Manufacturers, SIAM, overall passenger vehicle sales during the month rose 10.5 per cent. But motorcycle sales declined 5.9 per cent, while scooter sales increased 3.1 percent in December. Total two-wheeler sales in December declined 3.1 percent. Sales of commercial vehicles rose 11.5 percent during the month. Vehicle sales across categories declined marginally.