2018 U.S.-Booked Air Volume: $58 million
After debuting in the BTN 100 in 2015, pharmaceutical company Allergan saw its U.S.-booked air spend drop for the third consecutive year. BTN's estimated 2018 volume came in $6 million lower than 2017's spend. The steady decline wasn't unexpected, however. The Dublin-based maker of Botox and dozens of other drugs divested its generic pharmaceuticals business in 2016, nearly halving its workforce to 16,700 in the process. Allergan started growing again in 2017, adding about 1,100 jobs that year to reach 17,800, but the company cut that figure back down to 16,900 in 2018.