The bus manufacturing business is a graveyard over the past twenty years.  The author just named a few of the companies that have bit the dust since 1997. 

The problem with the American market is that its a zero-sum game. There have been many manufacturers that have gone after the smaller bus market. Thomas Bus of North Carolina formed a joint venture with Thomas Dennis of the U.K. in 1999 to built the U.S. version of Dennis' mid-size bus. They estimated the size of the market for these buses at 1,000. Thomas went out of the mid-size bus market after a few years. New Flyer's Midi bus is also based on an Alexander Dennis chassis built under license. With apologies to NFI, I suspect sales of this bus have been moderate.