The Mason City Globe Gazette reports (http://bit.ly/YivzH1) that the total was nearly 5,900 in 2012, compared with more than 11,400 in 2011.
The drop will prove costly to the airport, because the federal airport improvement subsidy of $1 million requires 10,000 passengers. The airport instead expects to get $150,000.
Great Lakes Airlines says it expects a loss of around $1.6 million for its first year of Mason City operation even after its essential air service subsidy of nearly $1.2 million.
Airport manager Pam Osgood says some problem arose after Great Lakes took over the service in April, including flights delayed or canceled because of mechanical problems.
She says those and other problems have declined since.
Information from: Globe Gazette, http://www.globegazette.com/