Is Dublin airport growth a threat to NI rivals?

Dublin was confirmed as Europe's fastest-growing major airport last week, as figures showed strong overall increases in Irish air traffic this year. And it seems many Northern Ireland flyers are choosing Dublin over our own airports. Between 2012 and 2014, there has been a 69% increase in the number of Northern Ireland residents using Dublin Airport. So what does this mean for Northern Ireland's two main airports - George Best Belfast City Airport and Belfast International?