Federal debt would be about one and one half times the size of the economy within 20 years under an alternative fiscal scenario from the Congressional Budget Office that assumes Congress will continue the recent tax cuts and spending increases enacted over the past year.

Debt held by the public, which excludes debt held by government accounts including the Social Security and Medicare trust funds, would top the previous World War II-era record of 106 percent of gross domestic product by fiscal 2029 under the CBO’s “extended alternative fiscal scenario,” released Wednesday.

That forecast would mean record debt levels are hit five years earlier than under the CBO’s baseline estimates, which assume the tax cuts for individuals enacted last December (PL 115-97) expire after 2025, and that discretionary spending declines starting in fiscal 2020 after the two-year budget deal enacted in February (PL 115-123) lapses. The alternative scenario also assumes dozens of expired tax “extenders” are made permanent, while several suspensions and delays of taxes imposed under the 2010 health care law (PL 111-148, PL 111-152) are also continued.

The heavier debt load would restrain economic growth, the agency said, while pushing up interest rates and making it more expensive for the Treasury to borrow in the future.

Deficits over the next decade, already projected to total $12.4 trillion, would rise by a further $2 trillion under the alternative scenario, and possibly as much as $3 trillion if lawmakers decide to hold the growth of tax revenue down by preventing more households from being pushed into higher tax brackets due to inflation.