▁a ▁drink ▁or ▁me al , ▁stating ▁that ▁ 1 5 % ▁of ▁establish ments ▁that ▁adopted ▁a ▁ban ▁in ▁ 2 0 0 7 ▁saw ▁turn over ▁fall ▁by ▁around ▁ 5 0 %. ▁However , ▁a ▁study ▁by ▁the ▁University ▁of ▁Hamburg ▁( A hl feld t ▁and ▁Ma enn ig ▁ 2 0 1 0 ) ▁finds ▁negative ▁impact s ▁on ▁reven ues , ▁if ▁any , ▁only ▁in ▁the ▁very ▁short ▁run . ▁In ▁the ▁medium ▁and ▁long ▁run , ▁a ▁recovery ▁of ▁reven ues ▁took ▁place . ▁These ▁results ▁suggest ▁either , ▁that ▁the ▁consumption ▁in ▁bars ▁and ▁restaur ants ▁is ▁not ▁affected ▁by ▁sm oking ▁b ans ▁in ▁the ▁long ▁run , ▁or , ▁that ▁negative ▁re venue ▁impact s ▁by ▁sm ok ers ▁are ▁compens ated ▁by ▁increasing ▁reven ues ▁through ▁non - sm ok ers . ▁Sm oking ▁is ▁not ▁permitted ▁in ▁any ▁public ▁trans it ▁or ▁in ▁or ▁around ▁railway ▁stations ▁except ▁for ▁the ▁locations ▁express ly ▁indicated ▁for ▁sm oking . ▁Sm oking ▁on ▁trains ▁was ▁b anned ▁completely ▁by ▁the ▁Deutsche ▁Bahn ▁AG ▁in ▁ 2 0 0 7 . ▁Sm oking ▁has ▁been ▁restricted ▁in ▁air ports ▁and ▁all ▁L uf th ans a ▁plan es ▁since ▁the ▁late ▁ 1 9 9 0 s . ▁ ▁The ▁ 2 0 0 6 ▁FIFA ▁World ▁cup ▁which ▁the ▁country ▁hosted ▁was ▁the ▁last ▁one ▁before ▁b ans ▁on ▁sm oking ▁in ▁c af es , ▁bars ▁and ▁restaur ants ▁were ▁introduced