In his 1954 book How to Lie with Statistics, Darrell Huff devoted a full chapter to “The Gee-Whiz Graph”—the trick of omitting zero from the vertical axis and stretching what’s left, to make a trend look steeper than it actually is.
We’re currently experiencing an outbreak of people applying this ploy to plots of one particular data set: historical per-capita energy use in the United States. Before this outbreak spreads any further, I’d like to at least document it.
First, here’s a straight plot of the data with a vertical axis that starts at zero (calibrated in two different unit systems for later comparisons):
There’s a lot to notice here! A long plateau at about 4 kilowatts during the 1800s. Dramatic upward spurts between 1897 and 1973, interrupted by temporary plateaus and a deep dip during the Great Depression. A peak at 12 kilowatts in 1979, followed by a gradual downward trend to the present level of about 10 kilowatts. (For comparison, the energy use rate of a typical adult’s food diet is about 0.1 kilowatts.)
If you want to understand this fascinating history, the best place to start is the work of Suits, Matteson, and Moyer, from whom I obtained most of the data.
On the other hand, to quote Huff:
“That is very well if all you want to do is convey information. But suppose you wish to win an argument, shock a reader, move him into action, sell him something. For that, this chart lacks schmaltz. Chop off the bottom.”
Planet Money
In 2013, Jacob Goldstein and Lam Thuy Vo of NPR’s Planet Money did just that, publishing a version of the graph with the bottom chopped off at 50 million Btu/year:
I don’t think these authors were trying to win any arguments, or to sell anything more than an innocent-seeming narrative—that there was a “200-year-long rise in per capita energy use”. But chopping off the bottom of the graph makes the rise appear about twice as dramatic as it actually was.
Besides having a chopped-off bottom, this version of the graph differs in some detailed, substantive ways from my version above. That’s because the Planet Money version uses an older and less complete data set that omits some important energy sources for the years before 1949, as explained here. Including all energy sources raises the 19th century plateau above 110 million Btu per year, and removes the abrupt uptick in 1850, which is an artifact of switching between two different underlying data sources.
To be clear, I don’t blame the Planet Money authors for using an older, incomplete data set, which was the only one conveniently available at the time. But they should have made sure they understood the limitations of their data, and been more suspicious of the 1850 uptick. Without that uptick, essentially all of their “200-year-long rise” occurs over less than 80 years. And by combining incomplete data with a chopped-off bottom, the Planet Money authors made a three-fold increase look superficially like an eight-fold increase. Gee whiz!
Flying Cars
Planet Money’s Gee-Whiz Energy Graph sat dormant, so far as I’m aware, between 2013 and 2020. Meanwhile, in 2018, another plot of the same data appeared. It came from computer scientist and futurist J. Storrs Hall, in his then-self-published book Where Is My Flying Car?. Hall chopped off the graph at 2 kilowatts (60 million Btu/year), again more than doubling the apparent relative increase:
Hall also put a smooth curve on the chart, intended to approximately fit the data up to about 1980. He named this curve after Henry Adams, an American historian who observed in 1907 that the world’s total coal power had been growing exponentially for several decades. Hall’s book says his smooth curve depicts “a 2 percent [annual] growth in actual energy consumed per capita”. To quote Duff again:
“That is impressive, isn’t it? Anyone looking at it can just feel prosperity throbbing in the arteries of the country.”
At first glance, Hall’s “Henry Adams curve” appears to be a pure exponential curve, representing a steady percentage growth rate. But this appearance is an illusion, caused by the graph’s chopped-off bottom. In fact, what Hall has plotted is a 2-percent exponential growth curve shifted upward by an additive constant of 2.5 kilowatts. The book is silent about this sleight of hand, though Hall confesses to it on his blog, where he tries to excuse the trick by arguing that fuel wood—America’s largest energy source until the 1880s—shouldn’t count as a source of energy. When we count all energy sources, the average growth rate from 1897 through 1973 comes to just 1.4 percent—not 2 percent. Over any time period longer than that, the average percentage growth rate was less.
For reference, here is a comparison of the data to some actual exponential growth curves:
No exponential curve fits the data very well, because this is a complex social system—not bacteria growing in a laboratory.
Unlike the Planet Money authors, Hall is definitely trying to sell us something. He says our failure to grow our energy use by 2 percent per year after the 1970s “had real and continuing consequences. There has been a marked drop-off in the technological advances that make a big difference in people’s lives—measured in productivity, health, and, yes, speed and ease of getting around.” Later in the book he writes, “To really reclaim our birthright and an optimistic future, we must get back on the Henry Adams Curve.”
Hall’s book got a publicity boost in November 2020, when Jason Crawford posted an enthusiastic review of it on his Roots of Progress blog. Crawford included Hall’s “Henry Adams curve” graph in his review, and posted the graph again in a follow-up article in February 2021. Crawford is explicitly trying to sell his readers on Hall’s narrative: “We should not seek to merely sustain current per-capita energy usage—we should get back on the Henry Adams Curve and increase it.” Whether we’re talking about energy, population, or technological progress, “Our baseline expectation should be no less than exponential growth.”
Exponential Growth
One quantity that has grown exponentially in recent years is the rate at which the Gee-Whiz Energy Graph keeps popping up. In December 2020, blogger Noah Smith revived the Planet Money version of the chopped-off graph in a Substack post decrying a “stagnation in energy technology” that began in the 1970s (and predicting that cheap wind and solar energy will end this stagnation). Smith doesn’t mention Hall or Crawford or exponential functions, though he does briefly mention flying cars—so the chain of influence isn’t completely clear.
In July 2021, economics journalist Ryan Avent used the same graph in a Substack post. He also mentions flying cars, and his message is similar to that of Hall and Crawford: “Increased energy use is essential to progress.”
Then pundit Matt Yglesias copied the Planet Money graph from Avent into an October 2021 Substack article titled “The case for more energy”. Yglesias doesn’t mention flying cars (or exponential functions) at all, but he does argue that geopolitical and pollution concerns “put us on an energy diet” starting in the 1970s, often preventing us from implementing “cool” inventions such as indoor farming, desalination, and direct removal of carbon dioxide from the air. He expresses the hope that we’ll be able to do all these things in the future, opening up “incredible new vistas”, by deploying zero-carbon energy sources on a massive scale.
In March 2022, Yglesias’s former Vox colleague Cleo Abram released a video based on his “more energy” article. Abram redrew the Planet Money graph, updating it with data through 2020, but continued to use incomplete data from the earlier years and again chose to chop off the bottom:
This graph appears in Abram’s fast-moving video for only a few seconds at a time, so the chance that a typical viewer would notice the chopped-off bottom seems slim. The video’s message is that as long as we can obtain the energy without releasing carbon dioxide, “everyone needs more energy”. As of this writing, the video has over 200,000 views on YouTube.
Over the last year the Gee-Whiz Energy Graph has also proliferated on social media, including tweets from Balaji Srinivasan, Last Contrarian, and Nan Ransohoff. Alec Stapp, co-founder of a new Washington, DC think tank called Institute for Progress, used the Planet Money version of the graph to take a dig at energy efficiency:
What finally provoked me to write this article, though, was the October 2022 special issue of the online publication Works in Progress. That issue, titled “Lost in Stagnation”, consists of six articles that all respond to Hall’s Flying Car book (published by Stripe Press in November 2021) in one way or another. Two of them, by Benjamin Reinhardt and Adam Hunt, feature a replotted version of Hall’s Henry Adams chart:
This version doesn’t even display a 2 kilowatt gridline, so you have to do a mental calculation to realize that the bottom has (yet again) been chopped off.
Both of the Works in Progress articles present this graph without any caveats. Reinhardt’s article, “Making energy too cheap to meter”, echoes Hall’s inaccurate claim in saying “If you plot historical energy use per person over time from the invention of the steam engine, it grew at about two percent per year for hundreds of years.” (This passage originally said the annual growth rate was a preposterous seven percent, as indicated in a “correction” at the bottom of the article.)
So that’s where we stand today: Four separately drawn versions of the Gee-Whiz Energy Graph, all with the bottoms chopped off to make the rise that ended in the 1970s seem bigger than it was. All four versions are being shown and spread to sell us on the idea that energy use goes hand in hand with prosperity, and therefore we should increase Americans’ energy use in the decades ahead.
So What?
I don’t want to exaggerate the harm done by deceptive presentations and interpretations of the Gee-Whiz Energy Graph. Even without the bottom chopped off, the graph shows a striking change during the 1970s, when a pattern of rapid (though lurching) increases in per-capita energy use switched to a pattern of gradual decline. Even though the period of rapid increases lasted less than a century, the changes in Americans’ everyday lives during that period were extraordinary.
But I think it’s notable that making these qualitative points hasn’t been good enough for any of the promulgators of the Gee-Whiz Energy Graph. They’ve all tried to add more quantitative juice to their narrative by displaying the graph in a distorted way.
Here’s my challenge to all such promulgators: Try to rewrite your narrative using an honest version of the U.S. per-capita energy use graph. Start your vertical axis at zero, and use a more complete data set. Acknowledge that the rise in per-capita energy use between 1800 and the 1970s was by a mere factor of 3. Acknowledge that no simple mathematical law can express the rate at which that growth progressed from each decade to the next. Acknowledge that the graph shows multiple time periods when Americans’ material lives improved even while per-capita energy use was not increasing. Then, with all these facts established, ask yourself: Does the rest of your narrative still hold up? If so, great! I’d like to read it. If not, maybe consider whether your worldview is too simplistic.
For what it’s worth, I don’t have my own simple narrative to replace the one I’m challenging. I disagree with a lot of that narrative, but not all of it. I’ll try to organize my thoughts enough to say more in future posts about the complex connections between energy, technology, and prosperity. My point at the moment is just that we can’t have fruitful discussions about these connections if we don’t first agree upon the verifiable facts.
Finally, I’d like to sincerely thank all the “promulgators” I’ve named above for raising fascinating questions and keeping this discussion going. Although I dislike their distortions, at least we agree that the questions are important.
[Revised 8 December 2022 to cite the article by Noah Smith, which I somehow forgot to mention in the original version of this article.]
