China has a population of just over 1.4 billion people with a density of 151 people per square kilometre, while the United States has a population of just over 347 million people with a density of 38 people per square kilometre1. Given the recent relatively rapid growth of the Chinese economy and its huge population it is likely that it will surpass the size of the US economy in the near future. There are several ways of measuring the size of an economy. They include:
Gross Domestic Product (GDP). This measures the monetary value of final goods and services—that is, those that are bought by the final user—produced in a country in a given period of time (e.g. a quarter or a year). It counts all of the output generated within the borders of a country. GDP is composed of goods and services produced for sale in the market and also includes some nonmarket production, such as defence or education services provided by the government2. The 2024 GDP of the US is about $29.2 trillion. In 2013 it was $16.9 trillion3. The GDP of China is about $18.7 trillion. In 2013 it was $9.7 trillion4. China’s GDP increased from roughly $400 billion in the early 1990s. At that time, its GDP was about 10% of US GDP; now it is about 64%. Given China’s relatively rapid and sustained economic momentum, it is inevitable that China’s GDP will overtake that of the US. This, of course, will be determined by the pace of US and Chinese nominal GDP growth as well as moves in the bilateral exchange rate. Citigroup analysts expect that overtaking will likely occur in the middle of the 2030s5.
Gross National Product (GNP). This alternative concept, counts all the output of the residents of a country. So if a German-owned company has a factory in the United States, the output of this factory would be included in US GDP, but in German GNP6. Large nations such as the US and China have a GNP very similar to their GDP.
Purchasing Power Parity (PPP). This is a macroeconomic tool that compares the buying power of different countries’ currencies using a common “basket of goods.” It shows the exchange rate at which the basket would cost the same in each country, making it easier to compare cost of living and overall economic strength. PPP adjusts for the difference in price levels between countries. To help facilitate this comparison, the University of Pennsylvania and the United Nations joined forces to establish the International Comparison Program (ICP) in 1968. With this program, the PPPs generated by the ICP have a basis in a worldwide price survey that compares the prices of hundreds of various goods and services. Thus, the program helps international macroeconomists estimate global productivity and growth. Every few years, the World Bank releases a report that compares the productivity and growth of various countries in terms of PPP and US dollars. Both the International Monetary Fund (IMF) and the Organisation for Economic Cooperation and Development Development (OECD) use weighted metrics based on PPP to make predictions and recommend economic policy7.
In terms of PPP, China is the largest economy in the world. As at April 2025, China’s PPP GDP is estimated to be larger than that of the US; China’s PPP GDP was approximately $40.72 trillion, while that of the US was about $30.51 trillion8. The reason this is so, is because goods and services are relatively cheaper in China and can be purchased in greater quantities, making its economic output appear larger when measured by what their money can buy locally rather than by market exchange rates.
The disparity between rich and poor in a nation is measured by the Gini Coefficient* with the higher number being indicative of greater income disparity. The Gini coefficient of China is 35.7, while that of the US it is 41.8 (Australia’s is 34.3, while in the Scandinavian countries the average is in the high 20s)9. Therefore, income disparity in the US is greater than in China. There are also indications that the poorest people in China are considerably better off than the poorest people in the US. This is indicated by the following statistics. The share of China’s national income earned by the top 10% of the population has increased from 27% in 1978 to 41% in 2015, nearing the US’s 45% and surpassing France’s 32%. Similarly, the wealth share of the top 10% of the population reached 67%, close to the US’s 72% and higher than France’s 50%. Meanwhile, income for China’s bottom 50% (539 million adults) increased fivefold since 1978 (albeit from a very low base) while the US saw a 1% decrease. The largest increase in inequality took place between the mid-1980s and the mid-2000s, and has apparently stabilised since then10.
While China is larger than the US when considering PPP, but has not yet eclipsed it in GDP, that is seemingly simply a matter of time. Indeed, it is quite likely that the Trump idiocy will hasten that eclipse. A straightforward illustration of one aspect of this idiocy should suffice because it will so obviously lead to long term damage of the US. It is what my field of expertise lies within: science. Science has long been a driver of US global pre-eminence. Now the fields of public health, climate science, environmental protection and nuclear safety, among numerous others have had billions in funding withdrawn and thousands of scientists sacked11. This purge in many fields is likely to take decades to restore if, indeed, that is possible.
While Canada and Europe and some parts of Asia have actively sought to attract scientists from the US, China seems to have done more. The Chinese government has for years looked for ways to attract talented international scientists, including the thousands of Chinese researchers who left the country to pursue advanced degrees in the US and other countries, many of whom went on to become pioneers and leaders in American science and technology12. Now China has introduced the ‘K visa’ that will allow young foreign researchers in science, technology, engineering and mathematics (STEM) to move there without having to secure a job first. Before the introduction of the K visa, most foreign STEM researchers hoping to move to China had to find a job in advance and then apply for a work visa. Foreign researchers who have graduated from ‘well known’ universities or institutes in China or abroad with a bachelor or higher degree in STEM will be eligible to apply. While China is opening its doors, the US is raising barriers, having recently imposed a $100,000 fee on applications for an H-1B visa which many STEM researchers need to enter the US13.
In his 2012 book ‘Strategic Vision’, former national security adviser Zbigniew Brzezinski said “Only by demonstrating the capacity for a superior performance of its societal system, can America restore its historical momentum, especially in the face of a China that is increasingly attractive to the third world”14.
Demonstrating the ‘capacity for a superior performance of its societal system’ seems like a forlorn hope in the face of the Trump idiocy. Indeed, the Trump idiocy will cripple the US for decades to come.
* The Gini coefficient, also called the Gini index or Gini ratio, is the most commonly used measure of income distribution—simply put, the higher the Gini coefficient, the greater the gap between the incomes of a country’s richest and poorest people. A country’s Gini coefficient is important because it helps identify high levels of income inequality, which can have several undesirable political and economic impact. These include slower GDP growth, reduced income mobility, greater household debt, political polarization, and higher poverty rates15.
Sources
- https://www.worldometers.info/world-population/population-by-country/#google_vignette
- https://www.investopedia.com/updates/purchasing-power-parity-ppp/
- https://tradingeconomics.com/united-states/gdp
- https://tradingeconomics.com/china/gdp
- https://www.citigroup.com/global/insights/when-will-china-s-gdp-surpass-the-us-and-what-will-it-mean-
- https://www.imf.org/en/Publications/fandd/issues/Series/Back-to-Basics/gross-domestic-product-GDP
- https://www.investopedia.com/updates/purchasing-power-parity-ppp/
- https://intelpoint.co/blogs/how-big-is-china-compared-to-the-us/
- https://worldpopulationreview.com/country-rankings/gini-coefficient-by-country
- https://sccei.fsi.stanford.edu/china-briefs/rise-wealth-private-property-and-income-inequality-china
- https://www.theguardian.com/us-news/2025/sep/17/trump-science-war-public-health-experts
- https://edition.cnn.com/2025/09/29/china/china-reverse-brain-drain-science-tech-competition-us-intl-hnk
- https://www.nature.com/articles/d41586-025-03657-6
- https://www.dymocks.com.au/strategic-vision-by-zbigniew-brzezinski-9780465061815#tab-label-description
- https://www.investopedia.com/terms/g/gini-index.asp
