Kwanchai Paphatphong, the organising chairman, said the drop was due to many factors, including the declining economy and the ongoing trade wars, which made people more cautious about spending.
Thirty four car exhibitors saw combined bookings declining by 15.2 per cent to 37,489. However, passenger car bookings rose slightly to 45.5 per cent from 38.9 per cent last year.
Toyota gained the highest overall car booking of 6,243 units, followed by Honda at 5,766, Mazda at 3,998, Isuzu at 3,716, and Mitsubishi at 2,959.
In the luxury segment, Mercedes-Benz topped the bookings with 1,862, followed by BMW with 969, Volvo with 474, Audi with 278, and Porsche with 257.
The motorcycle segment also saw a small drop to 7,251 booking