Courier and messenger jobs grew by 3,200 positions in July, according to The Wall Street Journal, citing data from the U.S. Bureau of Labor Statistics.
The number of jobs at delivery firms increased to a new high as well, rising to 669,200 and beating the previous record of 668,000 that was set in December of last year.
However, the source noted that warehousing organizations have had difficulty finding workers. Employment at these companies decreased by 2,200 positions in June.
Amazon has made headlines recently for its "Jobs Day" held on Aug. 2, when it held job fairs at warehouses and shipping centers across the country. The company intended to hire 50,000 warehouse, packaging and shipping support staff on that day, however, it has so far received 20,000 applications, according to Quartz.
Amazon stated that the 20,000 applications it did receive marked a company record for recruitment in a single day.
A competitive labor market has boosted wages for warehouse workers, Quartz noted, citing Wal-Mart which recently raised pay for many of its employees.
According to The Wall Street Journal, the warehousing sector has added 35,500 jobs in the past year.