NEW DELHI: Domestic passenger vehicle sales dropped by 23.69 per cent in September to 2,23,317 units, down from 2,92,660 units in the year-ago period, making it the 11th consecutive month of decline in vehicle off-take.Domestic car sales were down 33.4 per cent to 1,31,281 units last month as against 1,97,124 units in September 2018, according to data released by the Society of Indian Automobile Manufacturers (Siam) on Friday.Motorcycle sales last month declined 23.29 per cent to 10,43,624 units as against 13,60,415 units a year earlier.Total two-wheeler sales in September declined 22.09 per cent to 16,56,774 units compared to 21,26,445 units in the year-ago month.Sales of commercial vehicles were down 39.06 per cent to 58,419 units in September as compared with 95,870 units in the same period of last year, Siam said.Vehicle sales across categories registered a decline of 22.41 per cent to 20,04,932 units from 25,84,062 units in September 2018, it added.