It is always difficult to read statistics and more difficult to make them.
Yes the statistic for Icelandair shows 50% O&D traffic. But here we get to the problem with statistic regarding stop over.
We have people flying from an airport in North America to KEF
and a few days or perhaps weeks on to Europe or vice versa. How do we count O%D, when stopover and when transit. Is transit only when the passenger does not leave the airport? We do not have a category in statistics for stopover and how do we define it, how many days max?
We do not distinguish between O&D coming in one way and going out another way from coming from one place and going back to the same place.
So let us look at some facts regarding Icelandair and KEF
The yearly passenger numbers of KEF
are growing faster, 18 to 20% than Icelandair, 12 to 15%.
Most of the competition to Icelandair is seasonal, flying only from June to the beginning of September and serving the tourist trade.
Easyjet, Norwegian and WOWair are flying the year round but are mainly after O&D.
WOWair will try the transit market next year with flights from the UK to North America via KEF
Icelandair has been in the last years concentrated on growing the transit or connection business. Trying to get less seasonal and perhaps not fighting for every passenger in the season, but growing the business in the off season.
50% O&D can hide a lot of "stopover" passenger having a look at Iceland on a Europe or the other way USA trip.
So the counter move from Icelandair to Delta flying MSP
during the season, could be extending the time, for example starting in April or March and ending end of October, or going to around the year, and not increasing the frequency during the summer season to daily.