Despite an ongoing collapse in demand for air cargo, the loss of bellyhold space in passenger aircraft means that global freight capacity is still struggling to cope with the volume of goods that needs transporting, IATA data shows.

The airline association says that while global demand as measured by cargo tonne-kilometres fell 20.3% in May compared with the same period last year, global capacity slumped 34.7%.

For both demand and capacity, the reductions represent an improvement on April’s figures, down 25.6% and 41.6% respectively, but IATA notes that “capacity remains unable to meet demand as a result of the loss of belly cargo operations on passenger aircraft that have been parked”.

Director general Alexandre de Juniac states: “The gap between demand and capacity shows the challenge in finding the space on the aircraft still flying to get goods to market… The prospects for air cargo remain stronger than for the passenger business, but the future is very uncertain.

“Economic activity is picking up from April lows as some economies unlock. But predicting the length and depth of the recession remains difficult.”

Belly capacity for international cargo declined by two-thirds for May against the same month last year. Dedicated air cargo capacity increased by 25% as the industry made heavier use of freighters, but this was not enough to offset the lost volumes from passenger-aircraft groundings.

Cargo load factor rose 10.4 percentage points in May, which, IATA notes, indicates “pent-up demand” for air cargo that cannot be satisfied because of the ongoing groundings.

In terms of regional breakdowns, air cargo tonne-kilometres fell most sharply in Europe and Latin America, with declines of 29.5% and 28.3%. Asia-Pacific and the Middle East fared only slightly better. Capacity was down at least 26% in all regions, extending to 41.9% in Europe and 51.6% in Latin America.