Tracking Billionaire Wealth: Long-Term Projects & Datasets
World Inequality Database (WID.world)
The World Inequality Database (WID) is a globally recognized academic project tracking income and wealth distribution. It provides open-access data and interactive tools for comparing wealth across populations. WID incorporates billionaire wealth into its analyses to illuminate extreme wealth inequality. Notably, the World Inequality Report 2022highlighted that billionaire fortunes have grown much faster than average wealth: “The wealth of the richest individuals on earth has grown at 6–9% per year since 1995, whereas average wealth has grown at 3.2% per year. Since 1995, the share of global wealth possessed by billionaires has risen from 1% to over 3%.” This increase accelerated during the COVID-19 pandemic, which saw the largest recorded jump in billionaire wealth share .
Data & Coverage: WID offers data on wealth distribution for most countries, covering the entire spectrum from the bottom 50% to the top 0.001% (billionaires). In a recent methodology update, WID researchers compiled a country-by-country dataset of billionaire wealth (number of billionaires and their total net worth per country, 1995–2023) by harmonizing Forbes rich-list data . This ensures the top tail of wealth is captured in WID’s open data.
Interactive Tools: WID’s online platform includes a Wealth Comparator that lets individuals see where they rank in the wealth distribution. While primarily focused on percentiles, this tool implicitly benchmarks users against top wealth holders. WID’s data can be downloaded or accessed via an API, enabling reproducible research. All methodologies and assumptions are published transparently , addressing concerns that commercial billionaire rankings (Forbes, Bloomberg, etc.) lack full transparency .
Key Metrics: Users can explore metrics like the top 1% or top 0.01% wealth shares over time, the aggregate wealth of billionaires as a fraction of national or global wealth, and wealth growth rates by segment. For example, WID data shows how billionaire wealth grew ~2× faster than average wealth over the past ~25 years, contributing to the top 1% capturing ~38% of global wealth growth since 1995 .
Gapminder “Billionaires” Open Dataset
The Gapminder Foundation (a reputable NGO known for its data visualizations) maintains an open-source Billionaires Dataset that tracks billionaire net worth over time. This project is actively maintained and freely available on GitHub . Gapminder created it to provide a fact-based view of wealth extremes and to integrate billionaires into its famous “income mountain” charts of global income distribution.
Data Sources & Methodology: Gapminder scraped data from Forbes’ “World’s Billionaires” lists and the Hurun Global Rich List, then merged them into a single dataset . Each billionaire is assigned a unique ID, and duplicate entries (appearing in both Forbes and Hurun) were reconciled by keeping Forbes as primary . The dataset includes each billionaire’s name, age, country, source of wealth, and net worth as reported. All net worth figures from various years are normalized to constant 2011 USD for comparability . Notably, Gapminder also calculates a “daily income” from net worth by assuming a 3% annual return on assets – offering a tangible metric of how much income a fortune of that size could theoretically generate.
Coverage: The dataset currently covers 2002 through 2022 on an annual basis . It tracks the entry and exit of individual billionaires each year, allowing analysis of wealth trajectories over two decades. (For example, one can see how many billionaires existed in 2002 versus 2022, or how individual fortunes grew.)
Utility for Benchmarking: By including billionaires in its income distribution “mountain” charts, Gapminder helps ordinary individuals visualize where the wealthiest stand relative to everyone else. The data can be used to compare an average person’s income or wealth growth to the “billionaire index” – e.g. one could ask, “If my savings grew 5% a year, how does that compare to the 6–9% annual growth of billionaire wealth observed globally?” Gapminder’s open dataset and visualizations thus serve as a comparative tool, illustrating the gap between typical financial trajectories and the extreme top end. The data and code are openly accessible for anyone looking to reproduce or extend the analysis .
Forbes “World’s Billionaires” Lists (Annual & Real-Time)
Forbes magazine’s World’s Billionaires list is a well-known, long-running index of billionaire wealth. It is published annually (since 1987) and has become a de-facto data source for researchers and NGOs examining wealth inequality. In addition, Forbes runs a Real-Time Billionaires tracker online, updated daily, which monitors day-to-day net worth changes of the top several hundred richest individuals.
Trust & Popularity: Forbes’ billionaire data is widely cited in academic studies, NGO reports, and media articles. For example, Oxfam and the World Inequality Lab both utilize Forbes figures to highlight trends (with appropriate caveats on methodology). The Forbes list is considered long-term and continuously maintained – now in its 39th year, it recorded an all-time high of 3,028 billionaires in 2025 with a combined wealth of $16.1 trillion . These figures are often used as headline metrics for global wealth concentration.
Data & Methodology: Forbes employs researchers to value individuals’ assets (public holdings marked to market, private businesses estimated via revenue multiples, plus real estate, art, etc., minus debt) . The annual list provides each billionaire’s net worth snapshot (in USD) as of a certain date, along with age, nationality, and source of wealth. Forbes’ historical data allows tracking of wealth over decades – e.g. comparing the number of billionaires and total billionaire wealth now versus 10 or 20 years ago. (In 2001 there were under 600 billionaires; by 2025, over 3,000.) The criteria exclude royal families and heads of state where wealth is tied to position for consistency.
Key Metrics: Every annual release reports the total count of billionaires and aggregate net worth, plus year-over-year changes. For instance, the 2024 list identified 2,781 billionaires worth $14.2 trillion, up $2 trillion from the prior year . Forbes often highlights the biggest gainers or losers, new entrants, and the cutoff net worth for entry. This provides a benchmark against which one might compare broader economic trends (e.g., global GDP growth vs. billionaire wealth growth). While the raw Forbes data isn’t open-source, it is publicly reported and has been compiled into accessible formats by third parties (including Wikipedia tables and Kaggle datasets).
Bloomberg Billionaires Index
The Bloomberg Billionaires Index is another highly regarded tracker, maintained by Bloomberg News. Launched in 2012, it is an interactive daily ranking of the world’s 500 richest people. Bloomberg’s index is updated at the close of each trading day, reflecting stock price movements and other wealth events in near-real-time .
Features: The Bloomberg index provides a profile for each of the top 500 billionaires, including current net worth, one-day and year-to-date changes, source of wealth, and other details. Uniquely, it offers a comparison tool so users can select multiple billionaires and visualize their fortune sizes and changes side by side . This can serve as a benchmarking tool for curiosity (“How do two different tech moguls’ net worths compare over time?”) if not for personal finances directly. It is nonetheless a dramatic illustration of wealth velocity at the top.
Data Updates: Because it updates daily on trading days , the Bloomberg index effectively captures the volatility and momentum of billionaire wealth. For example, if tech stocks rally and add tens of billions to certain fortunes in a week, the index records that immediate surge. The index’s methodology draws from Bloomberg’s financial data terminals, estimating private asset values and using market prices for public holdings. It is maintained by a team of analysts, ensuring credibility.
Key Metrics: Bloomberg’s dashboard highlights metrics like each billionaire’s net worth (in USD), daily change (in dollars and percent), and rank. Aggregate statistics are also notable: as of late 2024, the total net worth of the Bloomberg Top 500 was about $9.8 trillion . Users can observe how much wealth is concentrated in just a few hundred individuals and how quickly it shifts. For instance, in 2021–2022, rapid market changes saw some top billionaires’ fortunes swing by tens of billions in months – an indicator of “wealth velocity” at the pinnacle.
Open Data Projects on GitHub & Kaggle
A number of open-source projects and community-contributed datasets have sprung up to facilitate analysis of billionaire wealth. These leverage publicly reported data (primarily Forbes) and often extend it or visualize it in novel ways. Such projects are valuable for researchers or individuals who want to reproduce analyses or benchmark their own wealth trajectory against billionaires over time.
Kaggle Datasets: On the data science platform Kaggle, users have compiled historical billionaire data. One example is “The World’s Billionaires Dataset 1987–2022”, which contains information on billionaires over 35 years. According to its documentation, this dataset includes each billionaire’s name, age, nationality, net worth, source of wealth, the year, and their ranking on the list . Another Kaggle dataset provides the Forbes 2024 list of 2,780+ billionaires in CSV form (with fields like country, industry, etc.). These datasets are not official but are openly shared and often updated when new Forbes lists come out . They enable anyone to perform exploratory analysis – for example, plotting the growth of total billionaire wealth vs. global median wealth, or examining turnover (how many new billionaires appear each year).
GitHub Projects: Developers and researchers have also created GitHub repositories analyzing wealth concentration. For instance, some projects focus on wealth distribution among billionaires (using code to parse Forbes data each year) and apply machine learning to find patterns in how billionaire fortunes grow. An example repository (RemleyGHooker/Wealth-Distribution-Among-Billionaires-Project) uses an “annually updated dataset on billionaires” to study statistical patterns and factors like age, self-made vs. inherited, etc., publishing the code and findings openly.
Reproducibility: Because these community datasets are accessible, they allow for transparent, reproducible analysis. Students, journalists, or curious individuals can use them to benchmark personal financial scenarios in context. For instance, one could calculate: “If I started with $10,000 in 2000 and grew my net worth by 5% yearly, I’d have ~$X today – whereas the average billionaire’s net worth grew much faster.” By drawing directly on the billionaire data, such comparisons become concrete. Tools like Jupyter notebooks (often shared on Kaggle/GitHub) show step-by-step how to make these calculations, fostering public understanding of wealth dynamics.
NGO & Advocacy Research (Oxfam, Inequality.org)
Global NGOs and inequality research groups actively track billionaire wealth as a bellwether of economic inequality, often releasing ongoing reports and interactive updates. While not always “datasets” in the open-data sense, these projects compile credible data (typically from Forbes or similar) into accessible indices and narratives that help the public benchmark their own situation against the ultrarich.
Oxfam’s Inequality Reports: Oxfam, an international NGO, publishes high-profile reports (often timed with the World Economic Forum at Davos) that use billionaire wealth as an inequality indicator. These reports are widely cited for statistics like the acceleration of billionaire wealth vs. stagnant poverty reduction. In 2024, Oxfam reported that the number of billionaires grew to 2,769 (from 2,565 in 2023), and their combined wealth surged from $13 trillion to $15 trillion in one year . They highlighted that the world’s ten richest men were gaining about $100 million a day on average during that period . Oxfam makes its methodology public (often a methodology note accompanies the report ), so others can see how the figures were derived (usually drawing on Forbes data and comparing it to broader economic data like World Bank poverty stats ).
Institute for Policy Studies (Inequality.org): In the U.S., the Institute for Policy Studies runs Inequality.org, which has an interactive billionaire wealth tracker updated periodically. They particularly track U.S. billionaire fortunes and their changes since the start of the COVID-19 pandemic. For example, IPS reported that from March 2020 to March 2024, the total wealth of U.S. billionaires jumped +87.6% (an increase of $2.58 trillion) – from roughly $2.95 trillion to $5.53 trillion . They provide running commentary and charts on how many new billionaires emerged and how concentrated wealth has become (e.g., the number of “centi-billionaires” worth over $100B). Such trackers help ordinary citizens put their own pandemic experience in perspective: while many struggled, the billionaire class saw enormous gains, quantifiable through these tools.
Purpose and Accessibility: These NGO-led projects use billionaire wealth as a comparative index to advocate for policy change. By showing, for instance, that billionaires’ wealth grew three times faster than the average in the past year , they enable readers to benchmark macro trends against their own stagnating wages or savings. Data transparency varies: some, like Inequality.org, directly cite sources and even link to Forbes’ real-time data , ensuring credibility. While the focus is on storytelling and advocacy, the underlying data is often available or reproducible from public sources, aligning with the goal of transparency and fact-based debate.
Sources
World Inequality Report 2022 – World Inequality Lab (Chapter 4: “Global wealth inequality: the rise of multimillionaires”)
WID.world Technical Note 2025-01 – World Inequality Lab (integration of Forbes billionaire data, 1995–2023)
Gapminder Billionaires Dataset Documentation – Gapminder.org
Forbes “The World’s Billionaires” 2024/2025 – Wikipedia summary of Forbes data
Bloomberg Billionaires Index – Wikipedia (overview and methodology)
Kaggle “World’s Billionaires Dataset 1987–2022” – LinkedIn article by dataset author
Oxfam Press Release (2024) – Oxfam International
“Billionaire Wealth: Pandemic Surge” – Inequality.org (Institute for Policy Studies)