"If the declining trend continues, many jobs would be affected as well as ancillary support services and auto parts makers," industry sources said.
They said the proliferation of second-hand vehicles has aggravated the already low demand for brand-new motor vehicles.
"Most of the second hand vehicles are imported from Japan and have been converted from right-hand to left-hand drive," sources said.
Based on Land Transportation Office (LTO) records, vehicle registrations went up sharply during the review period.
Brand new vehicles registered with the LTO account for only half of the new registrations, indicating that the other half are second-hand vehicles.
Passenger cars recorded the sharpest drop in demand, with sales plunging by more than 21 percent to 20,017 units in the first 100 months from 25,536 units in the same period last year.
In October alone, however, passenger car sales showed a slight increase of 0.9 percent from Septembers 2,090 units. But the figure was still 6.3 percent lower than 2,252 in October last year.
Sales of commercial vehicles managed to rise slightly to 46,663 units from 46,441 units a year ago.
Toyota Motor Phils. Corp. was still number one in terms of total industry sales, but has lost its grip on passenger car sales after grabbing the premiere spot from Honda Cars Philippines Inc. in September.
Honda regained its top position in terms of passengers car sales, but was only number three in terms of total industry sales.