Sorry David I totally misread the stats you provided.
27.6% isn't the best figure however with no advertising is it really a suprise. Of course a more frequent all year round service should be popular enough especially if it operated to Belfast City via Isle of Man as in 2011.
The figures in 2011 were better as the Welsh Operations Director at the time encouraged tour operators to offer packages ot the Isle of Man. I'm not sure if this was the case for 2012.