FRANKFURT - Global demand for air freight dropped in July, and slowing global trade means it will be difficult for cargo markets in the coming months, a leading trade body said on Friday. Air freight volumes dropped 0.6 percent in July compared with the previous year, against a rise of 1.2 percent for June, the International Air Transport Association said in its monthly air freight report. IATA said the declines came across all regions except Africa and the Middle East and that the most pronounced declines were in the Americas. “The combination of China’s continued shift towards domestic markets, wider weakness in emerging markets, and slowing global trade indicates that it will continue to be a rough ride for air cargo in the months to come,” IATA Director General Tony Tyler said in a statement. Separately, the association released passenger data for July, showing a rise of 8.2 percent in demand, measured by revenue passenger kilometres, boosted by a seasonal effect due to the timing of Ramadan this year.