A total of 124.4m tonnes were handled, a decline of 1% compared to the corresponding period in 2013.
Traffic had increased for the two previous quarters after generally declining from Q4 2011.
The second three-month period saw unitised traffic rise by 5% to 5.8m units.
That was the third consecutive quarter of growth.
Exports of units reached a five-year high at 2.8m units, an increase of 4% compared to the same period of 2013.
