SANTA MONICA, Calif. — This month's new-car sales (including fleet sales) are expected to be the highest of any month this year, with approximately 1.13 million units expected to roll out of showrooms in December.

This is a 10.2 percent increase from December 2009 and a 30.4 percent increase from November 2010, according to Edmunds.com. Retail sales are expected to be approximately 912,000 units, up from approximately 710,000 last month.

This year will close with a total of 11.5 million units sold which is a 10.5 percent increase from 2009’s 10.4 million.

Edmunds.com analysts predict that December's seasonally adjusted annualized rate (SAAR) will be the year’s highest, 12.34 million, up from 12.21 in November 2010. SAAR for retail sales increases from last month to about 10.1 million units.

Average automaker incentives in the U.S. are estimated to be $2,492 per vehicle sold in December 2010, up $28, or 1.1 percent, from November 2010, but down $62, or 2.4 percent, from December 2009.

“While we're far better off than a year ago and the trajectory is trending upward for a much brighter 2011, 2010 goes into the history books as the second worst year for car sales since 1982 – second only to 2009,” commented Edmunds.com Senior Analyst Michelle Krebs whose full forecast report can be found at here.

December 2010 had 27 selling days, one fewer than last December 2009. The chart below sets forth month-over-month comparisons:

“Two highly anticipated vehicles were launched this month: the Chevy Volt and the Nissan Leaf. Neither contributes much sales volume, but it should be good for the brands to have these green halo vehicles in the lineup and at dealerships,” noted Edmunds.com Analyst Ivan Drury.

The combined monthly U.S. market share for Chrysler, Ford and General Motors (GM) domestic nameplates is estimated to be 45.6 percent in December 2010, down from 46.1 percent in December 2009 but up from 44.4 percent in November 2010.

Edmunds.com predicts Chrysler will sell 96,800 units in December 2010, up 12.6 percent compared to December 2009 and up 32.1 percent from November 2010. This would result in a new car market share of 8.6 percent for Chrysler in December 2010, up from 8.4 percent in December 2009 and up from 8.5 percent as in November 2010.

Edmunds.com predicts Ford will sell 187,300 units in December 2010, up 5.1 percent compared to December 2009 and up 32.0 percent from November 2010. This would result in a new car market share of 16.6 percent of new car sales in December 2010 for Ford, down from 17.4 percent in December 2009 but up from 16.4 percent in November 2010.

Edmunds.com predicts GM will sell 230,100 units in December 2010, up 10.9 percent compared to December 2009 and up 36.4 percent from November 2010. GM's market share is expected to be 20.4 percent of new vehicle sales in December 2010, up from 20.3 percent in December 2009 and up from 19.5 percent in November 2010.

Edmunds.com predicts Honda will sell 114,100 units in December 2010, up 6.5 percent from December 2009 and up 27.3 percent from November 2010. Honda’s market share is expected to be 10.1 percent in December 2010, down from 10.5 percent in December 2009 and down from 10.4 percent in November 2010.

Edmunds.com predicts Nissan will sell 92,300 units in December 2010, up 25.9 percent from December 2009 and up 29.3 percent from November 2010. Nissan's market share is expected to be 8.2 percent in December 2010, up from 7.2 percent in December 2009 but down from 8.3 percent in November 2010.

Edmunds.com predicts Toyota will sell 164,900 units in December 2010, down 12.2 percent from December 2009 but up 27.5 percent from November 2010. Toyota's market share is expected to be 14.6 percent in December 2010, down from 18.4 percent in December 2009 and down from 15.0 percent in November 2010.