The Earth was 448.5 percent more abundant in 2021 than it was in 1980.
Gale L. Pooley, Marian L. Tupy —
Does population growth lead to greater resource scarcity, as argued by the English scholar Thomas Malthus and, more recently, by the Stanford University biologist Paul Ehrlich? Or does population growth coincide with, and perhaps even contribute to resource abundance, as the University of Maryland economist Julian Simon has argued? The Simon Abundance Index (SAI) measures the relationship between population growth and the abundance of 50 basic commodities, including food, energy, materials, minerals, and metals.
Main Findings
Global resource abundance fell by 22.6 percent in 2021, according to the fifth annual Simon Abundance Index. The base year of the index is 1980, and the base value of the index is 100. In 2021, the index stood at 548.5. In other words, the index rose by 448.5 percent over the last 41 years, implying a compound annual growth rate in global resource abundance of 4.24 percent and a doubling of global resource abundance every 16.7 years.
Figure 1: The Simon Abundance Index (1980–2021)
Analysis
The SAI is measured in time prices. To calculate a commodity’s time price, the nominal price of a commodity is divided by the global average nominal hourly wage. Over the last 41 years, the average nominal price of the 50 commodities rose by 103.9 percent, and the global average nominal hourly wage rose by 413.6 percent. So, the overall time price of the 50 commodities fell by 67.9 percent.
The personal resource abundance multiplier is calculated by dividing the average time price of the 50 commodities in 1980 by the average time price of the 50 commodities in 2021. The multiplier tells us how much more of a resource a person can get for the same hours of work between two points in time. The same number of hours of work that bought one unit in the basket of 50 commodities in 1980 bought 3.088 units in the same basket in 2021.
The resource abundance for the average inhabitant of the planet rose by 208.8 percent. The compound annual growth rate in personal resource abundance amounted to 2.79 percent, implying that personal resource abundance doubled every 25.2 years.
Over the last 41 years, the overall time price of the 50 commodities fell by 67.9 percent. Meanwhile, the world’s population increased by 77.6 percent. So, for every 1 percent increase in the world’s population, the average time price of the 50 commodities decreased by 0.88 percent (67.9 percent ÷ 77.6 percent = -0.88).
Note that the personal resource abundance analysis looks at resource abundance from the perspective of an individual human being. The question that we aim to answer is: “How much more abundant have resources become for the average inhabitant of the planet?”
Population resource abundance analysis, in contrast, allows us to quantify the relationship between global resource abundance and global population growth. You can think of the difference between the two levels of analysis by using a pizza analogy. Personal resource abundance measures the size of a slice of pizza per person. Population resource abundance measures the size of the entire pizza pie.
The population resource abundance multiplier is calculated by multiplying the change in personal resource abundance by the change in global population (3.088 x 1.776). The multiplier of 5.485 corresponds to the 548.5 value in the SAI 2022. It indicates an increase in the global resource abundance of 448.5 percent and a compound annual growth rate of 4.24 percent. Using these values, we can estimate that global resource abundance doubles every 16.7 years or so.
Figure 2: Visualization of the Relationship between Global Population Growth and Personal Resource Abundance of the 50 Basic Commodities (1980–2021)
Finally, let us say a few words about the resource abundance elasticity of population. In economics, elasticity measures one variable’s sensitivity to a change in another variable. If variable X changes by 10 percent, while variable Y, as a result of the change in X, changes by 5 percent, then the elasticity coefficient of X relative to Y is 2.0 (10 ÷ 5). A coefficient of 2.0 can be interpreted as a 2 percent change in X corresponding to a 1 percent change in Y.
We found that every 1 percent increase in population corresponded to an increase in personal resource abundance (the size of the slice of pizza) of 2.69 percent (208.8 ÷ 77.6). We also found that every 1 percent increase in population corresponded to an increase in population resource abundance (the size of the pizza pie) of 5.8 percent (448.5 ÷ 77.6).
Changes between 2020 and 2021
Over the last 12 months, the SAI declined from 708.4 to 548.5 (22.6 percent). This was the largest one-year drop recorded by the index. The largest previous one-year drop amounted to 11.3 percent in 2010. On average, the index increased by 4.69 percent a year between 1980 and 2021.
Figure 3: The Simon Abundance Index, Annual Percentage Change (1980–2021)
What accounts for the SAI decline between 2020 and 2021? First, although the long-term trend in resource abundance is a positive one, prices can and do move up as well as down. Julian Simon noted as much when he wrote in his 1996 book The Ultimate Resource 2,
There is no physical or economic reason why human resourcefulness and enterprise cannot forever continue to respond to impending shortages and existing problems with new expedients that, after an adjustment period, leave us better off than before the problem arose. . . . Adding more people will cause [short‐run] problems, but at the same time there will be more people to solve these problems and leave us with the bonus of lower costs and less scarcity in the long run. . . . The ultimate resource is people—skilled, spirited, and hopeful people who will exert their wills and imaginations for their own benefit, and so, inevitably, for the benefit of us all.
Second, prices and wages can be adversely affected by government policy. The COVID-19 pandemic–related restrictions on economic activity, for example, resulted in a supply shock from which many an industry is yet to fully recover. The supply shock was exacerbated by fiscal and monetary stimuli, which kept some workers from reentering the job market once the restrictions were lifted. These stimuli also resulted in a demand shock, with money flowing into real estate, the stock market, and commodities as savers attempted to protect themselves from rising inflation. Additional regulations on new resource exploration and production may have helped to reduce output, particularly in the energy sector. Finally, the spike in resource prices was greatly enhanced by the Russian invasion of Ukraine (although the conflict is not reflected in this year’s SAI).
Figure 4: The Simon Abundance Index, Percentage Change in Time Prices of the Main Resource Groups (2020–2021)
Third, humanity has experienced similar shocks and accompanying reductions in resource abundance before. Mercifully, history suggests that growth in the abundance of resources can be restored. The index, for example, grew by 28.4 percent, 20.0 percent, and 19.3 percent in 1986, 1985, and 2009, respectively. When government policies and proper monetary management encourage entrepreneurship, the discovery of new knowledge and creation of new wealth can return and flourish.
Figure 5: The Simon Abundance Index, Percentage Change in Time Prices of Individual Resources (2020–2021)
The Simon–Ehrlich wager and why predictions of resource scarcity keep getting it wrong.
Gale L. Pooley, Marian L. Tupy —
Summary: A famous bet between Julian Simon and Paul Ehrlich illustrates two ways of thinking about resources and human ingenuity. Ehrlich thought of resources as a fixed pie, while Simon believed that human beings would find ways to make resources more abundant. As Simon predicted, thanks to markets and human ingenuity, the resource prices that Simon and Ehrlich bet on fell over a decade.
One of the most important checks ever written in economics was for $576.07.
It arrived in the mailbox of Julian Simon, the University of Maryland economist and Cato Institute senior fellow, on an October morning in 1990. The envelope was plain. There was no return address. Inside was a check from Paul Ehrlich. Ehrlich, who died last week, was the Stanford biologist and author of the bestselling 1968 book The Population Bomb.
That small check settled one of the great arguments of the modern age.
Ehrlich had spent years warning that population growth would outrun the Earth’s resources, bring rising scarcity, and push humanity toward disaster. Simon believed the opposite. He argued that more people did not simply mean more mouths to feed. It also meant more minds to think, invent, and solve problems.
The dispute became so bitter that Simon proposed a bet.
“Pick any raw material,” he told Ehrlich, “and choose any future date. I’ll bet the price will go down.”
Ehrlich accepted. He and two colleagues selected five metals: copper, chromium, nickel, tin, and tungsten. They priced a basket of those commodities on Sept. 29, 1980, and agreed to compare the inflation-adjusted price 10 years later. If the real price rose, Simon would pay Ehrlich. If it fell, Ehrlich would pay Simon.
Ehrlich was certain that population growth would make resources scarcer and therefore more expensive. Simon was certain that human beings would find ways to make resources more abundant.
By Sept. 29, 1990, the world’s population had increased by about 850 million people, a rise of 19 percent. If the doomsayers were right, that should have pushed prices sharply upward.
It did not.
Inflation over the decade was 57 percent. Yet the nominal price of the five-metal basket barely budged, rising from $1,000 to $1,004. In real terms, the basket’s price fell by about 36 percent. Ehrlich mailed Simon the difference: $576.07.
That check mattered because it exposed a mistake that still poisons public debate.
The mistake is to think that natural resources are fixed gifts of nature and that economic life is therefore a grim contest over a pile that can only shrink as population grows. That view sounds sober. It is, in fact, blind to the central truth of human progress.
Resources are not simply things lying in the ground. Resources are matter plus knowledge.
Oil was once a nuisance that seeped into farmland and polluted water. A barrel of oil in the Stone Age was worthless. A barrel of oil in an industrial civilization could heat homes, move trucks, power factories, and feed chemical industries.
Nature gives us atoms. Human beings give those atoms value.
That is why Simon understood something Ehrlich missed. The ultimate resource is not copper or farmland. It is the human mind. More precisely, it is the human mind set free to experiment, trade, specialize, and innovate.
Freedom matters here. People do not solve problems automatically. They solve them when they are allowed to respond to scarcity with invention and enterprise. High prices invite substitution. Competition rewards efficiency. Property rights encourage investment. Markets spread information no planner can gather. Free people learn to do more with less.
This is not a fairy tale in which every problem solves itself. Pollution is real. Bad policy is real. Governments can strangle innovation, distort prices, and lock societies into waste and stagnation. Progress, in other words, is not guaranteed.
But the lesson of the Simon-Ehrlich bet is that the burden of proof belongs to the prophets of permanent scarcity. Time and again, they have underestimated human creativity and overestimated the world’s physical limits.
That is as true today as it was in 1980.
We hear that energy is running out, that growth must stop, that the planet cannot support prosperity for billions, and that human wants must be cut down to fit a closed and exhausted world. This language changes with the decade, but the instinct behind it is old. It treats people as liabilities. It imagines the future as a rationing exercise.
Simon offered a better vision. Human beings are not just consumers of resources. They are producers of ideas. They are creators of substitutes, technologies, and entirely new forms of wealth. They do not merely divide a pie. They learn how to bake bigger pies from ingredients earlier generations did not know they had.
The real contest, then, is not between population and resources. It is between two ways of seeing humanity.
One view sees every additional person as another claimant on scarcity. The other sees every additional person as a possible problem-solver, inventor, entrepreneur, scientist, or worker whose efforts can make life better for everyone else.
The check for $576.07 settled the bet. But the larger wager remains open.
Don’t bet against human beings, especially when they are free.
America’s Commodity Appetite: Evidence of Dematerialization
America's economy has never ceased to crave materials, but it has grown better at extracting more value from less stuff.
Marian L. Tupy —
Summary: A new study examines how the United States has shifted its material consumption patterns since 1900, showing a trend of “relative dematerialization” beginning around 1970. While certain commodities have grown in demand, many others have seen absolute declines due to technological advancements and efficiency improvements. Innovation and globalization have allowed the US economy to extract more value from fewer resources, raising questions about the long-term sustainability of this trend in an increasingly digital and energy-intensive world.
A new study by Iddo K. Wernick from the Rockefeller University’s Program for the Human Environment titled “Is America Dematerializing? Trends and Tradeoffs in Historic Demand for One Hundred Commodities in the United States” offers a remarkable portrait of how much the United States has changed in terms of material consumption since 1900.
The study examines the usage trends of 100 commodities—including iron ore, chickens, gallium, and titanium—and shows that a nation that started the 20th century with a seemingly bottomless appetite for raw materials pivoted dramatically around 1970. This pivot, which paradoxically coincided with the first Earth Day, marked a moment when the American economy began a decades-long march toward what Wernick calls “relative dematerialization.” In essence, “dematerialization” refers to the gradual uncoupling of resource use from economic growth.
In Superabundance: The Story of Population Growth, Innovation, and Human Flourishing on an Infinitely Bountiful Planet, Gale L. Pooley and I document a parallel phenomenon on the global stage, finding that resources become more abundant over time. Our key insight is that time prices—or the time required to earn the money to buy a specific good—have been falling for almost two centuries for almost all commodities. Although Wernick focuses on physical consumption patterns within the United States, his study corroborates a related idea: Increasing efficiencies allow Americans to produce or obtain more output from fewer inputs, which helps to keep price increases in check.
The Rockefeller paper breaks commodities into three groups based on their trends from 1970 to 2020. The first group consists of only eight commodities—including gallium, titanium, and chicken—for which demand grew faster than gross domestic product (GDP), showing that certain products vital to the modern economy (and the dinner table) can still outpace the broader economy. The use of the second group of 51 commodities, such as petroleum and nitrogen fertilizer, grew more slowly than overall GDP but increased in absolute terms. That relative decoupling translates to lower intensity of use: We consume more resources as our economy expands but less per dollar of economic output.
Finally, the use of the third group—41 commodities, including iron ore, cadmium, asbestos, and even water—experienced declines in both absolute consumption and intensity of use. According to Wernick, some of these, like asbestos, fell out of favor due to safety concerns, while others, like iron ore, lost ground because of new manufacturing technologies, such as electric arc furnaces, which made recycling more economical. Once indispensable commodities saw demand shrink, underlining the fact that most resources need not remain economically essential in the long run.
Wernick’s study also acknowledges the role of globalization in shifting the patterns of resource use: Certain energy-intensive or pollution-heavy production processes have migrated offshore, meaning the United States can appear more material-efficient while importing finished goods that embed resource usage from elsewhere. But that shift is neither absolute nor one way: The United States also exports large quantities of agricultural products, effectively shipping out “embodied” water, fertilizer, and cropland. These exchanges do not cancel each other out, but the global supply chain, which allows resources to flow to where they are most valued, benefits everyone.
Critics of this optimistic narrative often point to the “Jevons paradox,” whereby increased efficiency leads to cheaper commodities and triggers higher total consumption. The evolution of the American economy after 1970 certainly raises intriguing questions. Was relative dematerialization achieved at the cost of higher economic growth, which slowed around the first Earth Day? Is dematerialization a product of market-driven efficiencies or a result of government-imposed environmental laws and regulations?
Looking into the future, what will happen to American resource use as the United States becomes an information powerhouse? Although computing is electricity-intensive, it can create massive value with little use of physical commodities. And what if we are on the cusp of using incredibly dense fuels to generate that electricity, as the deals between tech companies and new nuclear companies might indicate?
The march of technological progress, combined with the deregulation and economic growth drives promised by the second Trump administration, may yet provide answers to those questions.
All told, Wernick’s findings confirm that, while the American economy has never ceased to crave materials—including metals, foods, and newly indispensable high-tech elements—it has grown better at extracting more value from less stuff. Our ingenuity is decoupling growth from sheer material input, though whether that trend can be sustained over the long run remains an open question.
Update on the Five Metals from the Simon–Ehrlich Bet
Since 1900, the average abundance of these five metals has increased 36.5 percent faster than the population.
Gale L. Pooley —
Summary: The Simon–Ehrlich wager famously demonstrated that population growth does not lead to resource scarcity but instead drives innovation and abundance. Since 1900, the production of five metals featured in the bet has risen dramatically. This bolsters Julian Simon’s argument that human ingenuity and technological progress enable us to produce more resources at lower costs, ensuring greater abundance even as populations grow.
Hannah Richie at OurWorldinData.org recently published an insightful article on the five metals featured in the Simon–Ehrlich wager. In 1990, Paul Ehrlich lost the 10-year bet and had to write a check to Julian Simon for $576.07. Simon had let Ehrlich pick the five metals in 1980 when the bet started. The payment reflected the inflation-adjusted decline of 36 percent in the average price of the five metals over the decade. This was despite an extraordinary global population increase during the 1980s of 850 million people (19 percent)—the largest growth in human history. Yet, even with this surge, resource prices dropped, reinforcing Simon’s argument that human population growth, coupled with ingenuity and the freedom to innovate, drives resource abundance rather than scarcity.
Richie highlights an important trend: The long-term abundance of these metals has increased significantly. Take a look at the staggering growth in their production since the early 1900s:
Between 1900 and 2000, the global population grew by 400 percent, from 1.6 billion to 8 billion. During the same period, the production of the five metals soared: Chromium increased by an astounding 78,082 percent, copper by 4,062 percent, nickel by 26,918 percent, tin by 226 percent, and tungsten by 4,829 percent. On average, production of these metals rose by 22,823 percent.
The relationship between population growth and resource production is captured by the production elasticity of the population. It is the ratio of the percentage change in production divided by the percentage change in population. On average, every 1 percent increase in population corresponded to a 57.06 percent increase in the production of these five metals.
In our book Superabundance, we compared the time prices of these five metals for blue-collar workers from 1900 to 2018 and have since updated the data to 2022.
The charts below detail the growth in abundance for each resource since 1900. Please note that vertical scales differ across the charts. The charts generally show the effects of 9/11, the financial crisis of 2008, and COVID-19 lockdown policies.
This table summarizes our findings.
From 1900 to 2022, the global population increased by 400 percent. Over the same period, the abundance of these five metals increased by an average of 546 percent, demonstrating that abundance has grown 36.5 percent faster than the population.
Some have suggested that Simon was just lucky. This is why looking at a much longer time period reveals underlying trends behind temporary fluctuations.
These data reinforce Simon’s prediction: The more people, the more we produce, and the lower the prices.
