Air cargo growth slowed in July due to a 23.6 percent dive in domestic mail.

Airlines carried a total of 975 million revenue ton miles of domestic cargo in July, up just 1.3 percent from a year earlier, according to figures released by the Air Transport Association.

International cargo grew to 1.17 billion RTMs, up 7.7 percent from a year earlier.

Combined domestic and international cargo for the year to date in July reached 15 billion RTMs, up 5.1 percent from a year earlier.