Irvine, California – Japan’s automakers are losing ground to their U.S. and Korean rivals due to vehicle supply interrupted by the Japanese earthquake, according to a new report by Kelley Blue Book.

September inventory figures for Japanese brands in the U.S. improved slightly over August, giving the first indication that the worst may be over, the report said. Overall, Japanese market share has declined four points since 2010, equating to a loss of more than 300,000 potential sales that were diverted primarily to the domestic and Korean manufacturers. The share in the ultra-competitive compact car, midsize car and compact crossover segments is down significantly for the Japanese, due to their inability to meet high demand as well as improved offerings from the competition.

Toyota and Honda suffered most from the earthquake, losing 2.5 and 1.5 points respectively, which allowed Hyundai, Chrysler and GM to each benefit by one point or more. The volume lost by Toyota and Honda equates to an approximate revenue shortfall of US$5 billion and $3.2 billion respectively.

GM has proven to be the primary beneficiary of Japan’s lost market share, increasing its share and subsequent sales by more than 130,000 units versus 2010, equating to an approximate increase of nearly $3 billion in gross revenue through August 2011. Hyundai has picked up close to 120,000 sales and $2.5 billion in gross revenue.

The report said that Japanese production should be hitting full steam right about now and the market is likely to see an influx of Japanese vehicles in the coming months.

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