In the near term, Trump's plans would provide the bigger goose for the economy, due to his aggressive tax cuts, but that would be mitigated down the road by a higher debt and deficit load, according to the group's most recent analysis released Monday.
As for Clinton, her tax increases would help boost fiscal health, but her spending plans on net would increase the national debt by $200 billion over 10 years. (Clinton repeatedly has said her spending platform is paid for, but virtually all independent analyses find her proposals would result in a slight debt increase.)
Trump's plan to repeal Obamacare would stimulate growth by incentivizing work, but overall his tax cuts would add $5.3 trillion to the debt, under numbers the committee arrived at using its own calculations and research by the Tax Policy Center. Trump has pledged that economic growth through lower regulation, decreased energy costs and elimination of the U.S. trade deficit would make the tax cuts revenue-neutral.
"A rapid acceleration of growth also leads to a significant reduction of our debt burden relative to GDP, and when Mr. Trump's spending cuts are added the plan achieves full revenue neutrality," Trump economic advisor Peter Navarro and businessman Wilbur Ross wrote in Tuesday's Wall Street Journal.
In a subsequent interview, Navarro dismissed the CRFB as a "sham group, because they don't really have any original analysis of their own." He said the committee relies on the Penn Wharton model, which doesn't take into consideration offsetting effects.
"It's analytical malfeasance at best and political malfeasance at worst," Navarro said.
The debt currently sits at $19.8 trillion, $14.3 trillion of which is held by the public, according to the Treasury Department. The budget deficit for the current fiscal year is $503 billion.
"These increases to the debt come on top of current law projections that show our debt growing by $9 trillion over the next decade," committee President Maya MacGuineas said in a post on the CRFB website. "It is clear we are on an unsustainable path and the candidates' failure to address this issue would have damaging consequences on the future of our economy and the financial well-being of all Americans."
The CRFB is a nonpartisan group of economic heavyweights dedicated to repairing the governmental balance sheet. Its co-chairs are Republican former Indiana Gov. Mitch Daniels; Leon Panetta, who served as former president Bill Clinton's chief of staff and as an official in the Obama administration; and Timothy Penny, a Democrat and former Minnesota congressman.
The committee estimates that Clinton's plan would take 0.4 percent points off gross domestic product in 2017 while Trump's would add 1.7 points. Over the longer term, though, the reduction from Clinton would come to just 0.1 points over 10 years, while Trump's debt increases would cut growth by 0.5 points. By 2036, the committee estimates Clinton's plan would add 0.5 points and Trump's cut growth by 4 points.
In sum, the committee's conclusions don't offer much optimism that the U.S. will break out of its slow-growth pattern. The current recovery is the worst since the Great Depression and comes amid generally lackluster growth around the world. Growth averaged just 1.1 percent in the first half of the year, and is on track for just 2 percent growth in the third quarter, according to the Atlanta Fed.
The Clinton campaign did not respond to a request for comment.
Correction: Mitch Daniels is a former governor of Indiana. An earlier version misstated his title.