WASHINGTON — The Congressional Budget Office cast doubt Thursday on the White House’s claim that President Trump’s proposed budget would balance in 10 years.

In its analysis of the spending plan Trump unveiled in May, the non-partisan budget office said that the deficit would shrink under the Trump budget but would still total $720 billion in 2027. The White House had projected a $16 billion surplus in 2027.

The difference is mostly Trump's economic optimism.

“The deficits that CBO estimates would occur under the president’s proposals are larger than those estimated by the administration,” the 23-page analysis concludes. “Nearly all of that difference arises because the administration projects higher revenue collections— stemming mainly from a projection of faster economic growth.”

The Trump administration had assumed 3% economic growth over the next decade. The CBO projects a more modest expansion of gross domestic product at an average annual rate of 1.9%.

The White House also claimed that the president's budget would lower public debt in 2027 to below 60% of the gross domestic product. The CBO analysis projected that debt that year would reach 80% of GDP.

The analysis comes just one day after the White House released a video accusing the CBO of inaccurately forecasting economic statistics in the health care legislation Republicans are trying to pass.

The Committee for a Responsible Federal Budget, a non-partisan, non-profit group, said the CBO report makes it clear just how hard it is to fix the debt without addressing the growth of Social Security and Medicare, the nation’s two largest spending programs.

“CBO’s analysis shows the president’s claim of a balanced budget is built on a house of cards, reinforced by economic growth rates that are far outside of the mainstream consensus and would be unprecedented given today’s demographic realities,” said Maya MacGuineas, the group’s president.

“We cannot just close our eyes, wish upon a star, and halt the aging of the workforce,” MacGuineas said. “To get even halfway to the president’s growth assumptions will require good luck, along with an aggressive combination of tax reform, regulatory reform, immigration reform, entitlement reform, and deficit reduction — all five of which are largely absent from the president’s budget.”

Congress has not yet taken action on the president's plan, but the fiscal year ends Sept. 30 and lawmakers must pass a spending bill before then to keep the government open.

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