Starr Martha A, Drake Keith
Department of Economics, American University, Washington DC, USA.
Greylock McKinnon Associates, Boston, Massachusetts, USA.
Tob Control. 2017 Mar;26(2):169-174. doi: 10.1136/tobaccocontrol-2015-052775. Epub 2016 Mar 25.
In 2010, the US Food and Drug Administration (FDA) proposed requiring tobacco companies to add graphic warning labels (GWLs) to cigarette packs. GWLs are large prominently placed warnings that use both text and photographic images to depict health risks of smoking. The companies challenged FDA's authority on First Amendment grounds; the courts accepted that FDA could compel companies to add GWLs, but argued that FDA had not established that GWLs would significantly reduce smoking.
This paper adds new evidence on the question of whether GWLs would have reduced cigarette demand, by examining whether tobacco companies' share prices fell unusually after news indicating a higher likelihood of having GWLs, and rose on the opposite news. Such findings would be expected if investors viewed GWLs as likely to reduce cigarette demand.
An event-study approach is used to determine whether the stock prices of US tobacco companies rose or fell unusually after news events in the period when GWLs were proposed, finalised, challenged and withdrawn.
Tobacco companies' stock prices indeed realised significant abnormal returns after GWL news, consistent with expected negative effects on cigarette demand. Our estimates suggest investors expected GWLs to reduce the number of smokers by an extra 2.4-6.9 million in the 10 years after the rule took effect.
These findings support the view that the GWLs proposed by FDA would have curbed cigarette consumption in the USA in an appreciable way.
2010年，美国食品药品监督管理局（FDA）提议要求烟草公司在香烟包装上添加图形警示标签（GWLs）。GWLs是显著放置的大幅警示，使用文字和图片来描绘吸烟的健康风险。烟草公司以第一修正案为由对FDA的权威提出质疑；法院认可FDA可以强制公司添加GWLs，但认为FDA没有证实GWLs会显著减少吸烟。
本文通过研究在有消息表明添加GWLs可能性增加后烟草公司股价是否异常下跌，以及在相反消息出现时股价是否上涨，为GWLs是否会减少香烟需求这一问题提供新证据。如果投资者认为GWLs可能会减少香烟需求，就会出现这样的结果。
采用事件研究法来确定在美国烟草公司股价在GWLs被提议、最终确定、受到质疑和撤回期间的新闻事件后是否异常上涨或下跌。
在GWLs相关新闻发布后，烟草公司股价确实实现了显著的异常回报，这与对香烟需求的预期负面影响一致。我们的估计表明，投资者预计在该规定生效后的10年里，GWLs将使吸烟者数量额外减少240万至690万。
这些研究结果支持了以下观点，即FDA提议的GWLs将在美国显著抑制香烟消费。
