Outpatient prescriptions, in defined daily doses per 1000 person-days, of the 10 antibiotics most commonly prescribed for (A) upper respiratory tract infections, (B) urinary tract infections, (C) lower respiratory tract infections and (D) skin/soft-tissue infections in 2006 and 2015. Note: TMP/SMX = trimethoprim-sulfamethoxazole, Amox/Clav = amoxicillin-clavulanic acid.