IATA announced global passenger traffic data for April showing that demand (measured in total revenue passenger kilometers or RPKs) rose by 4.6% the slowest pace since January 2015. April capacity (available seat kilometers or ASKs) increased by 4.9%, and load factor slipped 0.3 percentage points to 79.1%.

The disruptive impact of the Brussels Airport attack weighed on the April figures. IATA estimates that, absent the impact of the attacks, demand growth would have been around 5%.

“The disruptive impacts of the Brussels terror attacks will likely be short-lived. There are some longer-term clouds over the pace of demand growth. The stimulus from lower oil prices appears to be tapering off. And the global economic situation is subdued. Demand is still growing, but we may be shifting down a gear,” said Tony Tyler, IATA’s Director General and CEO.