DETROIT – Despite the tough American economy, General Motors Corp. has started the year off right – holding its share of the retail market in the first three months with a stable of strong new products such as the Chevy Malibu, Buick Enclave and Cadillac CTS.

GM captured 21.6 percent of retail sales in the U.S. market during the January-March period, according to the latest estimates provided exclusively to the Detroit Free Press by the Power Information Network, a subsidiary of J.D. Power and Associates.

Rivals Chrysler LLC and Ford Motor Co., meanwhile, performed poorly.

Chrysler lost 1.5 percentage points of share, ending with 9.8 percent. Ford dropped a little more than a half percentage point to 13.9 percent. Those are substantial declines when one considers that every percentage point of annual market share is about the equivalent of one assembly plant's full production for the year.

Retail sales are those made directly to consumers, and they exclude fleet sales to rental car companies, businesses and governments, which are typically sold at a discount. Industry experts view retail sales as one of the best measures of demand and future financial performance because they are generally more profitable.

Automakers release only their overall sales results, which combine retail and fleet performance, so the Power Information Network provides its own estimate of retail-only performance based on transaction data from more than 7,000 dealership franchises.

Japanese automakers, led by Honda Motor Co. and followed by Toyota Motor Corp. – both of which dominate lists of the nation's most fuel-efficient vehicles – picked up the 2.3 percentage points of retail market that Detroit lost and then some.

In all, Detroit's automakers now sell just 45.3 percent of the cars and trucks purchased by American consumers in dealer showrooms – a new low.

According to the estimates from Power, Detroit's automakers have sold less than half of the cars and trucks in America since the second quarter of 2006 and their collective grip on the American consumer has slipped further since then, despite GM's steady performance.

Among American consumers:

GM is still No. 1, followed by Toyota, which has 18.6 percent of the market.

Ford is No. 3, with Honda advancing quickly, with 12.4 percent of the market.

And Chrysler is No. 5, with Nissan not far behind.