IATA said despite the losses seen in the second quarter, cargo revenues rose 32% year-on-year, with increases across all regions (based on a sample of 66 airlines).

Cargo revenues were strong as demand for time-sensitive shipments was "alive".

IATA said carriers in some regions have converted passenger aircraft to freighter configurations to benefit from this. However, this was not enough to compensate for the decline in the belly capacity and yields remained high. 

It added that Asia Pacific cargo revenues rose 48%, the highest growth of any region, while North American revenue grew only 1%.