The Dow Jones Industrial Average (DJINDICES:^DJI)has pulled back more than 140 points, or 0.85%, in midafternoon trading despite some positive economic data. Initial unemployment claims fell by 2,000 to 339,000 last week  -- the figures remain in range with a growing labor market. Construction spending also rose more than expected, up 1% in November. In addition, the highly followed Institute for Supply Management manufacturing index fell slightly to 57 in December from 57.3 in November, which was better than the expected drop to 56.6; any reading above 50 indicates the U.S. manufacturing sector is expanding. Speaking of the manufacturing sector, major automakers will release December sales figures tomorrow.

Inside the Dow Jones, Boeing (NYSE:BA) is turning up the heat before members of the International Association of Machinists and Aerospace Workers vote on the company's latest contract offer tomorrow. The decision could be key to whether Boeing decides to build its new 777X aircraft in Everett, Wash., or take it elsewhere.

"They made it very clear that if there is a 'no' vote on the contract, they will not build the composite wing here," said Suzette Cooke, mayor of Kent, Wash., according to the Chicago Tribune. "It left the other parts of the plane in question."

Boeing is leveraging future job security to its Everett facility in return for switching workers' pension plan to a contribution, 401(k)-style plan, among other things. Investors would be wise to keep an eye on tomorrow's vote and subsequent decision of the 777X production and final assembly location. More than 20 states are competing for the work.

If the contract is rejected again, Boeing and its investors risk problems arising from moving production to another location with less experienced workers; that's something investors would prefer to avoid after Boeing's 787 Dreamliner had significant cost overruns and production delays.

Outside the Dow, Ford (NYSE:F), General Motors (NYSE:GM) and the rest of the automotive industry are expected to post strong December sales tomorrow morning. As you can see below, industry sales look to come in about 5% higher than last year, which would make 2013 the best year for auto sales since 2007 at about 15.6 million vehicles sold.

Information from 

Ford continues to gain market share in the U.S. and widened its brand lead over Toyota as the finishing touches were put on 2013. At the end of 2012 Toyota's brand trailed Ford sales by 322,521; the Blue Oval's lead widened to 388,825 entering December.

One reason for Ford's widening sales margin is its popular Fusion model. Fusion sales increased 22% through November, while Toyota's Camry sales have increased only 1.3%. The Camry still tops the sales chart for cars in the U.S., but the Fusion could continue eating its market share in 2014. The Fusion, in combination with the F-Series and Escape, continues to lead Ford's momentum and that's a trend you can expect to continue when Ford's next-generation 2015 F-150 hits the showrooms this year.