New Jersey-based Research firm Autodata said on Monday that US auto sales dropped for the 12th straight month in October to 838,156 from 1.23 million last year, the lowest monthly level since 1991.The seasonally adjusted annual sales rate for the month was 10.6 million down from 16.04 million a year ago. It is the worst seasonally adjusted annual rate of sales since February. Monthly auto sales in US were down 32% while seasonally adjusted annual sales rate slumped 37%.

The largest US automaker, General Motors (NYSE: GM), said its October US sales shrank 45% to 168,719 cars and trucks in October from 307,408 a year ago. Sales of light truck were down 51% to 97,119, while passenger car sales fell 34.3% to 73,466 vehicles. In a conference on Monday, GM Sales Chief Mark LaNeve said "In my 27 years (in the auto industry), I've never seen a month like this." GM's market share likely fell to around 20% in October. "Clearly we're in a very dire situation," said Mike DiGiovanni, GM executive director of global market and industry analysis.

The other two who make U.S. Big Three automakers- Ford (NYSE: F), and Chrysler, also saw their sales falling by double digits in October. Ford reported that it sold 132,838 cars and trucks last month, down 30.2% from 190,195 vehicles a year ago. Dearborn, Michigan based automaker reported that the combined car sales of Ford, Lincoln and Mercury fell 26.8% to 40,854 units. Demand for SUVs fell 54% while it was down 39% for crossover vehicles. Sales of F-Series pickups dropped 16.3% to 43,324 units.

Chrysler registered a 35% drop in sales to 94,530 vehicles. Vice president of marketing and communications Jim Farley said in a statement "Economic and market concerns have hurt the industry, along with harsher credit terms. We do not see near-term relief for Ford or its depressed shares."Chrysler said its October U.S. sales tumbled 35% to 94,530 vehicles. Demand for Chrysler's heavily-weighted truck lineup fell 34% while that for cars, it was down 37%.

Japanese and German automakers came up with equally disappointing October US car sales numbers.

Toyota (NYSE: TM), the largest Japanese automaker reported a 23% drop in car sales. The carmaker sold 152,101 vehicles in October compared to 197,592 a year ago.

Honda (NYSE: HMC) registered a 25.2% decline in demand. The automaker sold 85,864 vehicles, compared to 114,799 a year earlier.

Sales at Nissan Motors (NASDAQ: NSANY) were down 33% to 56,945 vehicles from 84,947 a year ago.

Among German automakers, Diamler (NYSE: DAI) posted a 24.5% decline in its US Sales. The company sold 17,232 units compared to 22,820 a year earlier. Sales of Mercedes brand fell 34.3% to 14,996. Porsche reported a steep drop of 50.1% in its US car sales. The German company sold 1,427 vehicles as against 2,862 in the same period, a year ago.

US Auto industry has been facing difficult times as crisis in credit markets has taken a heavy toll on it. October particularly turned out to be a difficult month it was marked by massive layoffs and drop in consumer spending. Credits almost dried up as turmoil in financial market claimed a number of large financial institutions. Meanwhile, Motor & Equipment Manufacturers Association (MEMA) has urged the Bush administration to come up with a plan for the auto industry along the lines of Troubled Asset Relief Program, passed by Congress last month to rescue U.S. financial institutions