Washington (CNN) The economic fallout of the coronavirus pandemic could nearly quadruple the federal budget deficit this year, pushing it to a whopping $3.7 trillion, according to a projection released Friday by the Congressional Budget Office.

Last year, with the economy still growing, the deficit surpassed $1 trillion for the first time since 2012 due in large part to Republican tax cuts passed in 2017.

What's more, the federal debt is projected to be 101% of US GDP by the end of September, the CBO said.

The agency warned that the outlook could be notably different by the end of the year depending on the trajectory of the pandemic.

Congress has already approved four economic stimulus packages since March, spending more than $2 trillion to try to keep the economy afloat by boosting unemployment benefits, expanding lending to small businesses, and sending out stimulus payments directly to American households. Lawmakers approved another $480 billion package this week to help hospitals and small businesses.

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