GENEVA — Hurricane Harvey’s devastating impact was felt not only on the ground but also in the air, says IATA in its August Airlines Financial Monitor Report.

According to the report, global airline share prices fell by 1.4% in August, the second consecutive monthly decline. August was also the second month in a row in which airline shares underperformed global equities.

The monthly decline in the global airline index was driven by a fall in North America, partly due to the disruptive impact of Hurricane Harvey as well as some renewed signs of pressure on unit revenues. In contrast, European and Asia Pacific airline shares rose solidly over the month (2.4% and 4.7%, respectively).

The good news is passenger yields have continued to trend upwards, albeit modestly, in recent months. The turnaround in the long-standing downward trend reflects a number of factors, including a stronger global economic backdrop as well upward pressure on some key input costs in a number of countries, including labour.

The recent weakness in the U.S. dollar means that the unadjusted yield exaggerates the upward trend in underlying yields in recent months. Nonetheless, when measured in constant exchange rate terms, passenger yields in June were 0.1% higher than in June 2016 – the strongest year-on-year growth rate since late-2013. Moreover, when measured on this basis, yields have trended upwards at an annualized pace of around 4% since early-2017.