What Really Happened After Raising the Smoking Age to 21? (Updated)

In 2014, New York City became the first major city in the USA to raise the tobacco purchase age to 21.  Prior to that, it was 18, much like the rest of the country.   The law was passed by Mayor Bloomberg at the end of 2013, and it went into effect in May 2014.

Since then, five states (California and Hawaii in 2016, New Jersey in 2017, and Maine and Oregon in 2018) and Guam (2018) have also raised it to 21 and numerous counties and towns/cities did so as well from 2013-2018, though a few localities had also done so earlier as well.  When Needham, MA did so in 2005-2008, there was much praise from the pro-21 crowd when surveys showed that teen smoking rates had dropped much faster in Needham than in its surrounding communities (which were 18) from 2006-2010.  So it is very curious indeed that no one seems to be talking about what happened anywhere else since they raised their own smoking ages to 21.

We think we know why.  At first glance, it does appear to have had some effect.  According to the CDC's Youth Risk Behavior Survey (YRBS), teen smoking rates did in fact drop from 2013 to 2015 in NYC:

2005   11.2%
2007   8.5%
2009   8.4%
2011   8.5%
2013   8.2%
2015   5.8%
2017   5.0%

Those are the percentages of combined 9-12 grade students who reported any current cigarette smoking in the past 30 days.  Looks impressive at first:  a relative 29% drop from 2013 to 2015.  But take a look at the same data for the nation as a whole, for comparison:

2005   23.0%
2007   20.0%
2009   19.5%
2011   18.1%
2013   15.7%
2015   10.8%
2017     8.8%

As you can see, the nation as a whole also saw a similar (if even faster) drop in teen smoking at the same time, with a relative 31% decrease from 2013 to 2015, despite no change in the smoking age in most places.  And the teen smoking rate in NYC was already much lower before the law change, having dropped more dramatically than the rest of the USA prior to 2007 and then remaining at a low level since.

How about San Francisco, another major city that raised its age limit to 21?

2005   10.9%
2007   8.0%
2009   10.4%
2011   10.7%
2013   7.5%
2015   5.4%
2017   4.7%

They also saw a similar size drop from 2013-2015, to the tune of 28% (vs. 29% in NYC and 31% in the USA overall).  Just one problem though.  San Francisco did not raise their smoking age until 2016, so these data show that the drop in the smoking rate happened while it was still 18, before the age limit was raised.  Thus, it would actually be part of the no-change control group, not the experimental group.  And if you include the decrease since 2011, San Francisco in fact saw more progress than NYC.  In fact, when we look at the 2017 data, we see that while the smoking rate continued to drop after San Francisco's age hike to 21 (and California's a month later), it seems to have dropped at a slower rate afterwards.

What about state-level data?  California's data from 2015 and 2017 show the following (the YRBSS has no state-level data for California before 2015 for this question):

2015  7.7%
2017  5.4%

That is a 29.9% drop, compared with an 18.6% drop for the nation as a whole for that two-year period.  But keep in mind that California also raised their cigarette tax by a whopping $2 per pack, effective April 1, 2017.  The YRBSS was taken after that, since the survey was done in the fall semester.  And cigarette taxes are well-known to reduce smoking, especially among young people, who are more price-sensitive.  Thus, California's smoking rate would have likely dropped just as fast without the age hike.

New Jersey has no post age-hike data yet.  But what about Hawaii, who raised their smoking age to 21 in early 2016 (but with no tax hike at all since 2011)?

2005   16.4%
2007   12.8%
2009   15.2%
2011   10.1%
2013   10.4%
2015   9.7%
2017   8.1%

Here we see a drop of 16.5% from 2015 to 2017, slower than the 18.6% drop for the nation as a whole.  Not very impressive.

And what about Pennsylvania, with no change in the age limit (18) but a $1 per pack cigarette tax hike in 2016, now just slightly below California's tax rate?

2009   18.4%
2015   12.9%
2017     8.7%

Here we see a drop of 32.6% (nearly a third) from 2015 to 2017, faster than the national drop of 18.6%, despite no change in the age limit and a tax hike only half the size of California's a year later.  In Philadelphia particularly it dropped by more than half, from 7.2% to 3.5% in those two years.  And the statewide drop from 2009 was likely at least partly a result of the federal cigarette tax hike that year as well.

Game. Set. Match.

Thus, we can conclude that the decrease in teen smoking in NYC and elsewhere following the hike in the purchase age was most likely NOT causally linked to it, and would most likely have occurred regardless given the above counterfactual data.  Kinda like we at Twenty-One Debunked initially predicted back in 2013 after first learning of the law change being proposed.  So if that wasn't the cause, what was?  Well, we know that nationwide, as well as in NYC, the secular trend for the past four decades (except a brief increase from 1992-1997) has been downward for both teen and adult smoking.  This was due to a general combination of education/awareness, taxation, regulation, and advertising restrictions, and the resulting cultural changes.  And in very recent years, electronic cigarettes have gained popularity as an alternative to combustible cigarettes, and in fact overtaking the latter and becoming at least twice as popular among high-schoolers by 2015.  Note that this was also true in NYC despite the 21 age limit applying to e-cigarettes as well.  And according to another CDC survey, the National Youth Tobacco Survey, the massive increase in vaping from 2011-2016 was in fact slightly outweighed by the decrease in combustible cigarette and cigar smoking, indicating a net displacement and substitution effect.

Interestingly, while the YRBSS did not ask about vaping until 2015, the data for 2015-2017 are quite instructive.  While the nation as a whole saw a modest but significant decrease in vaping from 2015 to 2017, California saw a smaller decrease than average and NYC saw a slight increase, as did Hawaii.  Likewise, Pennsylvania saw a larger than average decrease, which is not surprising given that they also significantly hiked their vape tax as well in 2016.  Though there are only two years of data, for 2017 these data are more reliable than the Monitoring the Future (MTF) survey since unlike MTF, there was no change in the question for the YRBSS.

Bottom line:  it looks like the supposed benefits of raising the smoking/vaping age to 21 were, shall we say, all smoke and mirrors.  The supposed success of Needham, MA was likely a statistical fluke and/or a result of endogeneity, much like the "early adopter" effects of the first few states to raise the drinking age to 21 creating that particular mirage in the 1980s.  Or perhaps increased enforcement in general relative to neighboring towns did the trick regardless of the age limit, like it did in Woodridge, IL and several other communities the 1990s with an age limit of 18.  Studies show that whenever vendor compliance exceeds 90-95%, there is indeed a dramatic drop in teen smoking regardless, by as much as 50% compared with previously weak enforcement and low compliance rates, especially for the youngest teens.

This all should be food for thought for policymakers debating not just the age limit for tobacco, but also for alcohol, cannabis, or anything else for that matter.  And even if such benefits of the 21 age limit were real, we at Twenty-One Debunked would still not support an age limit any higher than 18, on principle alone.  Old enough to fight and vote = old enough to drink and smoke.  'Nuff said.