FACTBOX: Key facts about September auto sales

(Reuters) - U.S. auto sales fell nearly 24 percent in September on an adjusted basis from a year earlier, according to data from auto manufacturers on Wednesday. The following are highlights from the largest carmakers in the U.S. market.

Overall industry

* Total light vehicle sales 964,873 units.

* Seasonally adjusted annualized sales rate 12.50 mln vs 16.19 mln a year earlier

General Motors Corp

* Light vehicle sales were down 15.6 percent, unadjusted. (282,806 units)

* Vehicle inventories at September-end: 717,000, down 179,000 vehicles from a year earlier

* Cars/trucks: Car sales down 9.8 percent/light truck sales down 19.3 percent

* Key vehicles: Chevrolet Impala up 17.1 percent, Chevrolet Malibu up 68.2 percent, Chevrolet Silverado down 3.9 percent, Chevrolet Tahoe down 52.2 percent, GMC Sierra up 1.6 percent.

* Incentives: average $3,972 per vehicle, up from $3,132 a year earlier.

* Year-to-date sales down 17.8 percent.

Toyota Motor Corp

* Vehicle sales down 29.5 percent on an adjusted basis (144,260 units)

* Cars/trucks: Car sales down 25.1 percent, trucks down 35.4 percent

* Key vehicles: Tundra down 59 percent, Camry down 24 percent, Prius down 9.3 percent, Corolla down 24.9 percent

* Incentives: averaged $1,481 per vehicle, up from $830 a year earlier.

* Year-to-date sales down 10.4 percent

Ford Motor Co

* Vehicle sales, excluding Volvo, fell 30.9 percent on an adjusted basis (116,356 units).

* Inventories at month-end 474,000 units, up from 461,000 a month ago

* Cars/trucks: Car sales fell 19.4 percent, total truck sales fell 39.5 percent

* Key vehicles: F-Series fell 41.6 percent, Explorer fell 67.3 percent, Expedition fell 37.4 percent, Focus rose 4.7 percent, Fusion fell 16.9 percent.

* Incentives: averaged $3,696 per vehicle, up from $3,101 a year earlier.

* Year-to-date sales down 17.1 percent

Honda Motor Co

* Vehicle sales down 20.9 percent on an adjusted basis (96,626 units)

* Cars/trucks: cars down 18.9 percent, trucks down 23.4 percent

* Key vehicles: Civic down 9.2 percent, Fit up 48.7 percent, Accord down 33.5 percent, Pilot down 12.6 percent, Odyssey down 31.8 percent

* Incentives: average $1,047 per vehicle, up from $1,023 a year earlier

* Year-to-date sales down 1.1 percent

Chrysler LLC

* Car and light truck sales down 30 percent on an adjusted basis(107,349 units)

* Cars/trucks: Car sales down 29 percent, truck sales down 34 percent

* Inventories at month-end 381,365 units, or 85-days supply.

* Key vehicles: Jeep Wrangler down 29 percent, Dodge Ram pickup down 31 percent, Dodge Caliber down 3 percent.

* Incentives: average $4,705 per vehicle, up from $3,713 a year earlier.

* Year-to-date sales down 25 percent

Nissan Motor Co Ltd

* Car and light truck sales down 34.2 percent on an adjusted basis (59,565 units).

* Cars/trucks: Cars down 33.8 percent, trucks down 41.6 percent.

* Key vehicles: Altima down 42.4 percent, Versa down 11.5 percent, Sentra down 34 percent, Titan down 44.7 percent, Murano down 15.8 percent.

* Incentives: average $2,376 per vehicle, up from $2,031 a year earlier.

Sources: Company releases. Autodata Corp and industry tracking firm Edmunds.com for incentives and market share.

September had 24 selling days, compared with 25 selling days in September 2007.

(Reporting by Poornima Gupta, David Bailey and Kevin Krolicki; Editing by Braden Reddall and Carol Bishopric)