Passenger traffic at Detroit airport down slightly ROMULUS, Mich. (AP) — Officials say passenger traffic at Detroit Metropolitan Airport fell slightly in 2012 from the previous year. The airport in Romulus announced Tuesday that preliminary numbers show it saw more than 32 million passengers, down less than 0.5 percent from 2011. International passenger traffic at the airport rose 6.8 percent to more than 2.8 million in 2012. And total cargo shipped at the airport increased 6 percent from 2011. ___ Online: http://www.metroairport.com