Estimating the U.S. national debt as a percentage of economic growth seems to have become something of a national pastime-one that is moving beyond data nerds.

Prediction-market platform Kalshi announced Thursday that it was releasing a 10-year debt-to-gross-domestic-product projection that is built on real-time, crowdsourced data and fiscal forecasts from the Congressional Budget Office (CBO). Kalshi's latest continuously updated projection has the 10-year public debt at 118% of GDP on Thursday.

That's a bit lower than the CBO's projection, which found that federal debt held by the public rises from 101% of GDP this year to 120% percent by 2036, according to the latest forecast released in February.

Specifically, the Kalshi's forecast is built on projections that track implied future outcomes on fed funds rates, inflation and real GDP growth, as well as long-term data on projected fed funds rates from overnight index swap $(OIS)$ markets and CBO's forecast on the primary deficit.

Kalshi touted its projection as an alternative to the existing forecasts because it uses crowdsourced, market-driven data.

"The CDF is not intended to replace other forecasts, such as the CBO's, but to serve as an additional data point that tracks the debt and wider fiscal outlook with a different methodology," the company said.

After the national debt hit $40 trillion in August, the Council on Foreign Relations estimated that debt-to-GDP ratio now stands at 125%

The International Monetary Fund and the live data from the U.S. Debt Clock estimates are both higher, putting the U.S. debt-to-GDP ratio at 126%.

With U.S. debt surpassing $40 trillion, the U.S. government is facing a fundamental structural imbalance between spending and revenue. The Peter G. Peterson Foundation cites several drivers of the higher debt level in recent years, including an aging population, rising healthcare costs, insufficient revenue, and higher interest rates.

In fact, the fiscal year to date interest expenses through July totaled $1.17 trillion, according to the U.S. Treasury fiscal data.

Since 2016, the national debt has surged by $20 trillion, split fairly evenly between Republican and Democrat administrations.

President Donald Trump has added about $11 trillion to the U.S. debt load across his two terms, Barron's previously reported. That's split between about $7.8 trillion during his first administration and $4 trillion since January 2025.